Download - DIY Cellphone

8/13/2019 DIY Cellphone

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DIY CellphoneThe DIY Cellphone is a working (albeit basic) cellphone that you can make yourself. It can make and receive

phone calls and text messages, store names and phone numbers, and display the time. It builds on the hardware

and software in theArduino GSM Shieldbut extends it with a full interface, including display, buttons, speaker,

microphone, etc. The source files for the cellphone are hosted on GitHub (hardware,software), which also

includes an issue list where you can file bug reports or request enhancements.

V A R I A T I O N S

There are two main variants of the DIY cellphone: one that uses a black and white LCD like those found on old

Nokia phones and one that uses an eight-character matrix of red LEDs. The LCD shows more information (six

lines of fourteen characters) but breaks over time. The variant with the LED matrix is harder to use but the display

is more robust.

M A K I N G T H E P H O N E

Making the DIY cellphone can be a fairly involved process but it doesn't necessarily require specific electronics

expertise. You'll need to order the circuit board and electronics components (about $200 total) and have access

to some other electronics tools. There's a good amount of fine hand soldering to be done: about 60 components,

mostly surface-mount, which can take from one to five or ten hours, depending on your experience. Programming

and, especially, debugging the phone can take a while again, depending on your experience and how much

goes wrong. Making the case requires some plywood and veneer, along with access to a laser cutter (or you can

find your own way to enclosure the circuit board). In short, this is a difficult but potentially do-able project.

O R D E R I N G T H E C I R C U I T B O A R D

You can order a version of the circuit board fromOSH Park.It costs about $60 and you get three copies of the

board.

OrderLCD variantfrom OSH Park. OrderLED matrix variantfrom OSH Park.Alternatively, you can upload the Gerber files to a fabrication service yourself, eitherOSH Park,Advanced

Circuits,AP Circuits,or a number of others. Each time I order boards, I save the Gerber files in my GitHub

repository, in a directory named according to the date. Find the latest here:LCD variant,LED matrix variant.

There are a few different files in the directory:

.cmp: top (component) side copper layer (i.e. the lines of copper forming the actual electronic connections onthe top side of the board)

.sol: bottom (solder) side copper layer (same, for the bottom of the board) .stc: top (component-side) solder mask (stop) layer (i.e. the green layer covering the copper) .sts: bottom (solder-side) solder mask (stop) layer .plc: top (component-side) silk screen (legend) layer, plus overall board dimensions (i.e. the white text on the

top of the board, plus a line indicating the overall board shape for which there isn't a separate file)

.pls: bottom (solder-side) silk screen (legend) layer (white text on the bottom of the board) .drd: (excellon) drill file (specifies where holes should be drilled in the board and how big they should be) .dri: drill tool file, often not needed (text description of the drill sizes used)You'll need to upload these (typically in a single zip file) and sometimes specify which file is what. This is a two-

layer board, 5.15" x 2.3", and the standard options for board thickness (0.62"), copper weight (1 oz), and solder

mask should be fine. You'll want to get solder mask and silk-screen on both sides. Getting the corners rounded

might count as a complex shape and cost extra; I think it's worth it but it's not necessary.

G E T T I N G T H E P A R T S

There's no kit available for the cellphone but you can order the parts from various websites.
http://arduino.cc/en/Main/ArduinoGSMShieldhttp://arduino.cc/en/Main/ArduinoGSMShieldhttp://arduino.cc/en/Main/ArduinoGSMShieldhttps://github.com/damellis/cellphone2hwhttps://github.com/damellis/cellphone2hwhttps://github.com/damellis/cellphone2hwhttps://github.com/damellis/cellphone2https://github.com/damellis/cellphone2https://github.com/damellis/cellphone2http://oshpark.com/http://oshpark.com/http://oshpark.com/http://oshpark.com/shared_projects/9KhdfD2Yhttp://oshpark.com/shared_projects/9KhdfD2Yhttp://oshpark.com/shared_projects/9KhdfD2Yhttp://oshpark.com/shared_projects/6Zg0GFONhttp://oshpark.com/shared_projects/6Zg0GFONhttp://oshpark.com/shared_projects/6Zg0GFONhttp://oshpark.com/http://oshpark.com/http://oshpark.com/http://www.4pcb.com/http://www.4pcb.com/http://www.4pcb.com/http://www.4pcb.com/http://www.apcircuits.com/http://www.apcircuits.com/http://www.apcircuits.com/https://github.com/damellis/cellphone2hw/tree/master/Eaglehttps://github.com/damellis/cellphone2hw/tree/master/Eaglehttps://github.com/damellis/cellphone2hw/tree/master/Eaglehttps://github.com/damellis/cellphone2hw/tree/led-matrix/Eaglehttps://github.com/damellis/cellphone2hw/tree/led-matrix/Eaglehttps://github.com/damellis/cellphone2hw/tree/led-matrix/Eaglehttps://github.com/damellis/cellphone2hw/tree/led-matrix/Eaglehttps://github.com/damellis/cellphone2hw/tree/master/Eaglehttp://www.apcircuits.com/http://www.4pcb.com/http://www.4pcb.com/http://oshpark.com/http://oshpark.com/shared_projects/6Zg0GFONhttp://oshpark.com/shared_projects/9KhdfD2Yhttp://oshpark.com/https://github.com/damellis/cellphone2https://github.com/damellis/cellphone2hwhttp://arduino.cc/en/Main/ArduinoGSMShield


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Electronic Components

Most of the electronic components are available fromSparkFunandDigi-Key.You'll also need to get theM10

GSM Modulefrom the Arduino store.

Bill of Materials:BOM.pdf(LCD variant),BOM.pdf(LED matrix variant)

Tools

To assemble the phone, you'll a need a good soldering setup: a soldering iron (e.g. the WES51)with a good tip,fine-pitch solder, desolder wick, tweezers, etc. To program the microcontroller, you'll need an AVR in-system

programmer (like theAVRISP mkII)and a3.3V FTDI Cable(or equivalent breakout board). To charge the battery,

you'll need a mini-USB cable.

To make the laser-cut case, you'll need access to a laser cutter and a small philips screwdriver.

SIM Card

The phone should work with a full-size SIM card from any GSM provider. I've been using T-Mobile in the United

States but the phone has also been tested with AT&T and in India, China, and Europe.

Other Materials

For the laser cut enclosure, you'll need:

A sheet of 1/4" / 6 mm plywood, like thiscraft plywood from Midwest Productsavailable at many art supplystores. (Avoid the micro-lite aircraft plywood from Midwest Products or other plywood with dark adhesive

layers as they tend to burn in the laser-cutter.)

A sheet of wood veneer, preferably with adhesive backing. Six M0, 5/8", pan-head machine screws (e.g. this100 pack from McMaster-Carr) Six M0 nuts (e.g. this50 pack from McMaster-Carr)Or, try making a difference enclosure (e.g. with 3D-printing or by milling a mold).

Images of the assembled circuit boards (LCD variant). Click to enlarge.

Images of the assembled circuit boards (LED matrix variant). Click to enlarge.

S O L D E R I N G T H E E L E C T R O N I C S
http://www.sparkfun.com/http://www.sparkfun.com/http://www.sparkfun.com/http://www.digikey.com/http://www.digikey.com/http://www.digikey.com/http://store.arduino.cc/ww/index.php?main_page=product_info&cPath=6_33&products_id=289http://store.arduino.cc/ww/index.php?main_page=product_info&cPath=6_33&products_id=289http://store.arduino.cc/ww/index.php?main_page=product_info&cPath=6_33&products_id=289http://store.arduino.cc/ww/index.php?main_page=product_info&cPath=6_33&products_id=289https://github.com/damellis/cellphone2hw/blob/master/Components/BOM.pdf?raw=truehttps://github.com/damellis/cellphone2hw/blob/master/Components/BOM.pdf?raw=truehttps://github.com/damellis/cellphone2hw/blob/master/Components/BOM.pdf?raw=truehttps://github.com/damellis/cellphone2hw/blob/led-matrix/Components/BOM.pdf?raw=truehttps://github.com/damellis/cellphone2hw/blob/led-matrix/Components/BOM.pdf?raw=truehttps://github.com/damellis/cellphone2hw/blob/led-matrix/Components/BOM.pdf?raw=truehttp://www.digikey.com/product-detail/en/WES51/WES51-120V-ND/526397http://www.digikey.com/product-detail/en/WES51/WES51-120V-ND/526397http://www.digikey.com/product-detail/en/WES51/WES51-120V-ND/526397http://www.digikey.com/product-detail/en/ATAVRISP2/ATAVRISP2-ND/898891http://www.digikey.com/product-detail/en/ATAVRISP2/ATAVRISP2-ND/898891http://www.digikey.com/product-detail/en/ATAVRISP2/ATAVRISP2-ND/898891http://www.digikey.com/product-detail/en/TTL-232R-3V3/768-1015-ND/1836393http://www.digikey.com/product-detail/en/TTL-232R-3V3/768-1015-ND/1836393http://www.digikey.com/product-detail/en/TTL-232R-3V3/768-1015-ND/1836393http://www.midwestproducts.com/store/product/3282e69c-13f4-452f-9906-a40c0a5a9d8a/6mm_14_x_12_x_12_Craft_Plywood.aspxhttp://www.midwestproducts.com/store/product/3282e69c-13f4-452f-9906-a40c0a5a9d8a/6mm_14_x_12_x_12_Craft_Plywood.aspxhttp://www.midwestproducts.com/store/product/3282e69c-13f4-452f-9906-a40c0a5a9d8a/6mm_14_x_12_x_12_Craft_Plywood.aspxhttp://www.mcmaster.com/#91772A060http://www.mcmaster.com/#91772A060http://www.mcmaster.com/#91772A060http://www.mcmaster.com/#90730A001http://www.mcmaster.com/#90730A001http://www.mcmaster.com/#90730A001http://www.flickr.com/photos/mellis/9162546146/http://www.flickr.com/photos/mellis/9160323897/http://www.flickr.com/photos/mellis/8383433747/http://www.flickr.com/photos/mellis/8384518274/http://www.flickr.com/photos/mellis/9162546146/http://www.flickr.com/photos/mellis/9160323897/http://www.flickr.com/photos/mellis/8383433747/http://www.flickr.com/photos/mellis/8384518274/http://www.flickr.com/photos/mellis/9162546146/http://www.flickr.com/photos/mellis/9160323897/http://www.flickr.com/photos/mellis/8383433747/http://www.flickr.com/photos/mellis/8384518274/http://www.flickr.com/photos/mellis/9162546146/http://www.flickr.com/photos/mellis/9160323897/http://www.flickr.com/photos/mellis/8383433747/http://www.flickr.com/photos/mellis/8384518274/http://www.mcmaster.com/#90730A001http://www.mcmaster.com/#91772A060http://www.midwestproducts.com/store/product/3282e69c-13f4-452f-9906-a40c0a5a9d8a/6mm_14_x_12_x_12_Craft_Plywood.aspxhttp://www.digikey.com/product-detail/en/TTL-232R-3V3/768-1015-ND/1836393http://www.digikey.com/product-detail/en/ATAVRISP2/ATAVRISP2-ND/898891http://www.digikey.com/product-detail/en/WES51/WES51-120V-ND/526397https://github.com/damellis/cellphone2hw/blob/led-matrix/Components/BOM.pdf?raw=truehttps://github.com/damellis/cellphone2hw/blob/master/Components/BOM.pdf?raw=truehttp://store.arduino.cc/ww/index.php?main_page=product_info&cPath=6_33&products_id=289http://store.arduino.cc/ww/index.php?main_page=product_info&cPath=6_33&products_id=289http://www.digikey.com/http://www.sparkfun.com/


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While the cellphone uses many small, surface-mount components, it's possible to solder it together by hand with

a good soldering iron and some practice. Most of the components are straightforward to solder (apart from their

small size), with a few exceptions:

Capacitors: Be careful of the polarity on the large (1000 uF) capacitors, they may explode if you solder thembackwards. Use the orange stripe to orient them correctly.

Polarity: Other components with polarity include the super-capacitor, the LEDs (note the two small green dotson one side), the ATmega1284P microcontroller (note the circle in one corner), the M10 GSM module (which

has an arrow in one corner), the SIM card socket, the microphone, and the diode (note the faint grey line on

one side). These components have no polarity (can be soldered either way around): the crystal (8 MHz),

speaker, reset button, small capacitors, and resistors. Other components only physically align in one

orientation (but make sure the transistors aren't upside down and that the buttons aren't rotated 90 degrees).

Antenna: When soldering the antenna, start with the pad that faces the GSM module. That's the one thatcarries the electrical signal; the others are simply there for structural support (to hold the antenna down). You

may even be able to heat the solder on that pad from the top of the antenna, the heat can be conducted

through the two vias (small holes) in it.

Solder Jumpers: There are two solder jumpers on the bottom of the board, labelled "Cell" and "uC". Solder thecenter pad of each to the pad labelled "uC". (This connects the RX and TX lines from the FTDI header to the

ATmega1284P on the board so that they communicate over serial. If you instead solder the center pad to the

"Cell" pad, the FTDI cable connects directly to the GSM module so that you can communicate with it from the

computer.)

Speaker: The speaker is awkward to solder because it has no legs. First, apply solder to the pads on thePCB. Then rest the speaker on top of the PCB (aligning its pads with those on the board) and solder it from

the bottom. You can feed in solder or melt the pre-applied solder from below. If it doesn't work, don't remove

the speaker(you might rip its pads off). Instead, try to re-melt the solder on its pads by inserting the iron into

the holes from below.

USB Connector: Only the two outer (of the five small) legs of the USB connector are used, so you don't haveto solder the three central legs. (Do solder the four corners, though, they provide structural support).

ISP Header: Because you only need to burn the bootloader once, I typically don't solder pins into the ISP(2x3) header. Instead, you can insert pins into the connector on your ISP and hold them against the pins (from

the top of the board) while you burn the bootloader. If you have trouble, you can solder pins to the holes but

you'll have to adjust the case to make room for it.

LCD(LCD variant only): You only need to solder the eight pins at the top of the screen, not the eight pins onthe bottom. To solder them, insert male header pins from the bottom (so that their plastic portion is under the

board). First solder them to the PCB, then put the display on top (verifying its orientation). Then solder the

pins to the display.

C O M P I L I N G T H E S O F T W A R E

The cellphone's software is an Arduino program that makes use of various libraries and a third-party hardware

definition. You can compile and upload it with the Arduino software but some initial setup is required:

1. Download and install Arduino 1.0.4 (tested) or 1.0.5 from theArduino software page.2. Install theGit version control software.See, for example, the instructions from GitHub forWindowsorMac.3. Checkout the cellphone's source codefrom GitHub,e.g. "git clone https://github.com/damellis/cellphone2.git".

Then "cd cellphone2" to change into the source code's directory.

4. Checkout the other repositories used by the cellphone's software with "git submodule init" and "git submoduleupdate".

5. For the LED matrix variant, checkout the LED matrix branch with "git checkout led-matrix". (The code for theLCD variant is stored in the default master branch.)

6. Run Arduino and, in the preferences dialog, set your sketchbook folder to the cellphone2 directory (that youchecked out from github).
http://arduino.cc/en/Main/Softwarehttp://arduino.cc/en/Main/Softwarehttp://arduino.cc/en/Main/Softwarehttp://git-scm.com/http://git-scm.com/http://git-scm.com/https://help.github.com/articles/set-up-git#platform-windowshttps://help.github.com/articles/set-up-git#platform-windowshttps://help.github.com/articles/set-up-git#platform-windowshttps://help.github.com/articles/set-up-git#platform-machttps://help.github.com/articles/set-up-git#platform-machttps://help.github.com/articles/set-up-git#platform-machttps://github.com/damellis/cellphone2https://github.com/damellis/cellphone2https://github.com/damellis/cellphone2https://github.com/damellis/cellphone2https://help.github.com/articles/set-up-git#platform-machttps://help.github.com/articles/set-up-git#platform-windowshttp://git-scm.com/http://arduino.cc/en/Main/Software


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7. Also in the preferences dialog, enable verbose information on compile and upload. (This will help you debug ifanything goes wrong.)

8. Restart the Arduino software.9. Select "DIY Cellphone" from the Tools > Board menu.10. Select AVRISP mkII (or whichever programmer you're using) from the Tools > Programmer menu.11. Plug the LiPo battery into the cellphone.12. Initiate "Burn Bootloader" from the Tools menu (while holding the pins in the ISP header against the

corresponding holes in the PCB). This may take a few minutes.

13. Connect the 3.3V FTDI cable to the FTDI header (the black wire goes on the side labelled "B", the green onthe side labelled "G").

14. Open the Cellphone sketch from the sketchbook.15. From the Tools > Serial Port menu, select the item corresponding to the FTDI cable.16. Upload the Cellphone sketch.17. The screen should turn on and show the word "connecting".18. Insert a SIM card into the socket.19. It may take a while for the cellphone to connect to the network. If it doesn't connect after a few minutes, try

resetting the board (by pressing the small reset button). You can see debugging information in the Arduinoserial monitor at 9600 baud.

20. Once the phone connects to the network, you'll see the words "connected" and "caching" on the screen. Aftera few seconds, the screen will go blank. That's a sign that the phone has successfully started up and is now

on the lock screen. See "using the phone" below for more information.

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unlock

The unlocking screen (backlight will be off)

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lock menu

The home screen

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back call

The dialing screen

U S I N G T H E P H O N E

Unlocking the Phone

Once the phone successfully starts up, it will be locked and the screen will be blank. To unlock the phone, press

any button; the date and time will appear on the screen for a few seconds (this is the "unlocking" screen). On the

LED matrix variant, the date and time will scroll back and forth across the screen. If, during this time, you press

the "unlock" key (the top-left button), the phone will unlock and, if using the LCD variant, the screen's backlight

will turn on. On the LCD variant, the date and time will remain on-screen, and the soft-keys labels will read "lock"

and "menu". On the LED matrix variant, the time will remain on the display, without scrolling. This is the home

screen.


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Locking the Phone

From the home screen, you can lock the phone by pressing the left soft-key button (the upper-left button). The

screen and backlight will turn off but the phone will still be on and able to receive phone calls or text messages.

Adjusting the Contrast/Brightness

When the phone is in the "unlocking" screen, you can adjust the contrast (for the LCD variant) or brightness (forthe LED matrix variant) by using the up and down buttons (the two central buttons of the group of four buttons

just below the screen).

Dialing a Phone Number

You can dial a number from the home screen. Simply press the button corresponding to the first digit of the

number. You'll be taken to the dialing screen where you can enter the rest of the number. Press * to delete the

last digit entered or "back" (the left soft-key) to go back to the home screen. By pressing # one or more times in

succession, you can enter #, *, or +. To call the number, press the right soft-key ("call").

Using the Phone Book (Contact List)

From the home screen, press the down arrow (the lower of the group of four buttons just below the display) toenter the phone book. Use the down and up arrows to navigate to the desired entry. Press the right soft-key

("okay") to enter a menu from which you can call that contact, send a text message to that contact, add a new

entry to the address book, or edit or delete the contact.

Adding a Contact

To add a contact, first enter the contact list by pressing the down arrow from the home screen. Then press the

right button to enter the contact menu ("call", "text", "add entry", etc); scroll (using the down and up buttons) down

to the "add entry" menu item and press the right button. Now you can enter the name of the contact using the

keypad (2 is "abc", 3 is "def", etc.; 1 is space, * is backspace, and # is shift). Once you've entered the contact's

name, press the down arrow to move to the field for entering the contact's phone number. (You can press the up

arrow to return to the field for entering the contact's name.) Enter the contact's number using the keypad (* isagain backspace, but # now cycles between #, *, and +). When you've entered both the name and phone

number, press the right button to save the contact (or the left button to cancel).

Calling a Contact

To call a contact in your contact list, scroll to that contact, press the right button to bring up the contact menu

("call", "text, etc.) and then press the right button again to call.

Texting a Contact

To text a contact, scroll to their entry in your contact list and press the right button to bring up the contact menu.

Scroll down to "text" and press the right button. Now you can enter your message using the keypad. (As for

entering a contact's name, 2 is "abc", 3 is "def", etc.; 1 is space, * is backspace, and # is shift.) Press the rightbutton to send the text (or the left button to cancel).

T R O U B L E S H O O T I N G

There are a lot of pieces and, therefore, a lot of things that might not work. Here are some potential problems and

some possible solutions.

Can't burn the bootloader onto the microcontroller.

Does the microcontroller have power? (Is the battery is plugged in and charged?) Are the legs of the microcontroller soldered correctly (i.e. is each leg actually soldered to the corresponding

pad and are the legs free of shorts / solder bridges)? In particular, check the legs connected to the ISP

header, to VCC, and to ground.


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Are the pins in the header of the ISP being held firmly against the corresponding holes on the board? Youmight try soldering pins into the ISP header (on top of the board).

Is the crystal soldered correctly? (If not, the first step of burning the bootloader might succeed but the secondone might fail.)

Can't compile the cellphone program.

Are you using Arduino 1.0.4 or 1.0.5? Did you checkout the submodules of the cellphone2 repository? (They contain the required libraries and board

definition.)

Is the Arduino sketchbook folder set to the cellphone2 folder? (Otherwise, the Arduino software won't be ableto find the libraries and the board definition.)

Is "DIY Cellphone" selected from the Tools > Board menu?Can't upload the cellphone program.

Is the FTDI cable connected correctly (black wire to side labelled "B"; green wire to "G")? Did you select the right serial port from the Tools > Serial Port menu? (Try unplugging the FTDI cable and see

which item disappears from the menu; that's the one corresponding to the cable.)

Are the solder jumpers soldered correctly (central pad connected to the "uC" pad)? Is the board powered? Is the FTDI header soldered correctly? The 0.1 uF capacitors near it? The RX and TX legs of the

microcontroller?

Is the crystal still soldered correctly? Did the bootloader burn successfully? (If not, see that issue above.)Can't connect to the network.

Is there a SIM card in the socket? Is the SIM socket soldered correctly? The 22 ohm resistors? The corresponding pads on the GSM module? Is the antenna soldered correctly? The corresponding pad on the GSM module? Is the 0 ohm resistor soldered correctly (to the trace connecting the M10 GSM module to the antenna)? Do you have reception? Is the SIM card locked to another phone? AT&T (and possibly other carriers): have you activated your SIM card and phone on AT&T's website? You'll

need the IMEI number printed on the M10 GSM module.

Another component doesn't work (e.g. display, speaker, microphone, buzzer).

Is the component soldered correctly? Are the connected components (e.g. the corresponding legs of the microcontroller or GSM module) soldered

correctly?

S E R I A L D E B U G G I N G

You can further debug the phone by communicating with the GSM module via serial communication with the

computer, using the microcontroller as a proxy. To do so, upload the SerialProxy sketch to the phone (using a

3.3V FTDI cable or breakout board). Then open the serial monitor and set the baud rate to 9600 and the line

ending to "carriage return". After a few seconds, you should see:

READY

AT

OK

That means the GSM is ready to receive AT commands (text strings that mostly start with the letters "AT"). The

commands are detailed in thedatasheet for the GSM modulebut here are a few basic ones:

AT

Test/synchronization command. If you enter "AT" in the serial monitor (with a "carriage return" line

ending), you should get a response of "OK".

AT+CREG?
http://arduino.cc/en/uploads/Main/Quectel_M10_AT_commands.pdfhttp://arduino.cc/en/uploads/Main/Quectel_M10_AT_commands.pdfhttp://arduino.cc/en/uploads/Main/Quectel_M10_AT_commands.pdfhttp://arduino.cc/en/uploads/Main/Quectel_M10_AT_commands.pdf


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Check the status of the network registration (connection). The response will be in the form "+CREG

0,N", with N being: 0 (not registered to a network), 1 (registered to a network), 2 (searching for

networks), 3 (network registration denied), or 5 (registered, roaming).

AT+CPBS?

Display currently-selected phone book. Sample response: "+CPBS: "SM",50,250", with the "SM"indicating the SIM card is the current phone book (some other options include "MC" for the missed call

list, "RC" for the received call list, and "ME" for the GSM module phone-book) and that 50 of its 250

entries are in use. This command can be useful for verifying that the GSM module is able to

communicate with the SIM card.

AT+CPBS="SM"

Select the SIM card's phone book. You can also replace the "SM" with the abbreviations for the other

phone books listed previously.

AT+CPBR=1

Read the first entry from the currently-selected phone book. Replace the 1 with the number of the entryyou wish to read (up to the total phone book size reported by AT+CPBS?).

M A K I N G T H E E N C L O S U R E

You can make a simple but functional enclosure from laser-cut plywood and veneer, along with some small

screws (see materials above):

1. Before cutting the case, check that the case files match the circuit board. In particular, I've made a lot oftweaks to the size and location of the screw holes, so check that they're in the same place on the PCB and

the case. (Note that the holes in the bottom veneer file should be bigger than the others, this is to

accommodate the nut, recessing it slightly.)

2. If you soldered pins onto the ISP header, you'll need to cutout a space for them in the top piece of plywood.Edit DIY-Cellphone-Top accordingly.

3. Laser-cut the plywood (1/4" / 6mm) using the DIY-Cellphone-Top and DIY-Cellphone-Bottom files in theCase/folderof the damellis/cellphone2hw repository on GitHub. The SVG files were created in Inkscape, then

exported to hpgl for importing to CorelDraw.

4. Laser-cut the veneer using the DIY-Cellphone-Top-Veneer and DIY-Cellphone-Bottom-Veneer files. Cut theveneer with the wood front facing up (adhesive back face down).

5. Remove the adhesive backing from the top veneer piece and stick it to the outer face of the top plywoodpiece. Repeat with the back, again attaching the veneer to the outer face of the plywood.

6. There's a bit of empty space between the top of each button and the veneer. You might need to stick smallspacers to the back of the top piece of veneer, one for each button (in the middle of each rectangular flexure

cutout in the veneer). That way, you don't have to depress the veneer as much to press the button.7. Slip the top and bottom pieces of the case over the circuit board. You'll have to fit the battery's wire in

between the GSM module and the battery connector, folding it in half. The plywood pieces should rest flat

against the circuit board.

8. Insert the six screws and thread them onto the nuts.D E S I G N F I L E S

The design files and source code for the cellphone can be found on GitHub:

David A. Mellis
https://github.com/damellis/cellphone2hw/tree/master/Casehttps://github.com/damellis/cellphone2hw/tree/master/Casehttps://github.com/damellis/cellphone2hw/tree/master/Casehttps://github.com/damellis/cellphone2hw/tree/master/Casehttp://web.media.mit.edu/~mellis/index.htmlhttp://web.media.mit.edu/~mellis/index.htmlhttps://github.com/damellis/cellphone2hw/tree/master/Casehttps://github.com/damellis/cellphone2hw/tree/master/Case


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Click an image see a larger version;more photosare on Flickr.

V A R I A T I O N S

Above Left: cardboard enclosure by Jeff Warren. Above Right: purpleheart enclosure by Dena Molnar. Below

Left: milled enclosure by Yoav Sterman. Below Right: 3D-printed enclosure by Ben Peters.

P R E S S

Wired UK:How to make your own mobile phoneby Tom Cheshire (Nov. 12, 2012)

New Scientist:Making your own phone is easier than you might think,Lisa Grossman (Mar. 21, 2013)

ABC News:Make Your Own Cellphone for $120 in Parts, Plus SIM Card: It's Not Rocket Science,Karin Halperin

(Apr. 23, 2013)

DIY Cellphone
http://www.flickr.com/photos/mellis/sets/72157629294902700/http://www.flickr.com/photos/mellis/sets/72157629294902700/http://www.flickr.com/photos/mellis/sets/72157629294902700/http://www.wired.co.uk/magazine/archive/2012/11/play/make-your-own-mobile-phonehttp://www.wired.co.uk/magazine/archive/2012/11/play/make-your-own-mobile-phonehttp://www.wired.co.uk/magazine/archive/2012/11/play/make-your-own-mobile-phonehttp://www.newscientist.com/article/mg21729096.000-making-your-own-phone-is-easier-than-you-might-think.htmlhttp://www.newscientist.com/article/mg21729096.000-making-your-own-phone-is-easier-than-you-might-think.htmlhttp://www.newscientist.com/article/mg21729096.000-making-your-own-phone-is-easier-than-you-might-think.htmlhttp://abcnews.go.com/Technology/build-cell-phone/story?id=18952735http://abcnews.go.com/Technology/build-cell-phone/story?id=18952735http://abcnews.go.com/Technology/build-cell-phone/story?id=18952735http://www.flickr.com/photos/mellis/8428228990/http://www.flickr.com/photos/mellis/8430303229/http://www.flickr.com/photos/mellis/9058290161/http://www.flickr.com/photos/mellis/9060713963/http://www.flickr.com/photos/mellis/8725022595/in/set-72157629294902700http://www.flickr.com/photos/mellis/8447674795/in/set-72157632698042046http://www.flickr.com/photos/mellis/8384518044/in/set-72157629294902700/http://www.flickr.com/photos/mellis/9511241570/http://www.flickr.com/photos/mellis/8428228990/http://www.flickr.com/photos/mellis/8430303229/http://www.flickr.com/photos/mellis/9058290161/http://www.flickr.com/photos/mellis/9060713963/http://www.flickr.com/photos/mellis/8725022595/in/set-72157629294902700http://www.flickr.com/photos/mellis/8447674795/in/set-72157632698042046http://www.flickr.com/photos/mellis/8384518044/in/set-72157629294902700/http://www.flickr.com/photos/mellis/9511241570/http://www.flickr.com/photos/mellis/8428228990/http://www.flickr.com/photos/mellis/8430303229/http://www.flickr.com/photos/mellis/9058290161/http://www.flickr.com/photos/mellis/9060713963/http://www.flickr.com/photos/mellis/8725022595/in/set-72157629294902700http://www.flickr.com/photos/mellis/8447674795/in/set-72157632698042046http://www.flickr.com/photos/mellis/8384518044/in/set-72157629294902700/http://www.flickr.com/photos/mellis/9511241570/http://www.flickr.com/photos/mellis/8428228990/http://www.flickr.com/photos/mellis/8430303229/http://www.flickr.com/photos/mellis/9058290161/http://www.flickr.com/photos/mellis/9060713963/http://www.flickr.com/photos/mellis/8725022595/in/set-72157629294902700http://www.flickr.com/photos/mellis/8447674795/in/set-72157632698042046http://www.flickr.com/photos/mellis/8384518044/in/set-72157629294902700/http://www.flickr.com/photos/mellis/9511241570/http://www.flickr.com/photos/mellis/8428228990/http://www.flickr.com/photos/mellis/8430303229/http://www.flickr.com/photos/mellis/9058290161/http://www.flickr.com/photos/mellis/9060713963/http://www.flickr.com/photos/mellis/8725022595/in/set-72157629294902700http://www.flickr.com/photos/mellis/8447674795/in/set-72157632698042046http://www.flickr.com/photos/mellis/8384518044/in/set-72157629294902700/http://www.flickr.com/photos/mellis/9511241570/http://www.flickr.com/photos/mellis/8428228990/http://www.flickr.com/photos/mellis/8430303229/http://www.flickr.com/photos/mellis/9058290161/http://www.flickr.com/photos/mellis/9060713963/http://www.flickr.com/photos/mellis/8725022595/in/set-72157629294902700http://www.flickr.com/photos/mellis/8447674795/in/set-72157632698042046http://www.flickr.com/photos/mellis/8384518044/in/set-72157629294902700/http://www.flickr.com/photos/mellis/9511241570/http://www.flickr.com/photos/mellis/8428228990/http://www.flickr.com/photos/mellis/8430303229/http://www.flickr.com/photos/mellis/9058290161/http://www.flickr.com/photos/mellis/9060713963/http://www.flickr.com/photos/mellis/8725022595/in/set-72157629294902700http://www.flickr.com/photos/mellis/8447674795/in/set-72157632698042046http://www.flickr.com/photos/mellis/8384518044/in/set-72157629294902700/http://www.flickr.com/photos/mellis/9511241570/http://www.flickr.com/photos/mellis/8428228990/http://www.flickr.com/photos/mellis/8430303229/http://www.flickr.com/photos/mellis/9058290161/http://www.flickr.com/photos/mellis/9060713963/http://www.flickr.com/photos/mellis/8725022595/in/set-72157629294902700http://www.flickr.com/photos/mellis/8447674795/in/set-72157632698042046http://www.flickr.com/photos/mellis/8384518044/in/set-72157629294902700/http://www.flickr.com/photos/mellis/9511241570/http://abcnews.go.com/Technology/build-cell-phone/story?id=18952735http://www.newscientist.com/article/mg21729096.000-making-your-own-phone-is-easier-than-you-might-think.htmlhttp://www.wired.co.uk/magazine/archive/2012/11/play/make-your-own-mobile-phonehttp://www.flickr.com/photos/mellis/sets/72157629294902700/


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The DIY Cellphone is a working (albeit basic) cellphone that you can make yourself. It can make and receive

phone calls and text messages, store names and phone numbers, and display the time. It builds on the hardware

and software in theArduino GSM Shieldbut extends it with a full interface, including display, buttons, speaker,

microphone, etc. The source files for the cellphone are hosted on GitHub (hardware,software), which also

includes an issue list where you can file bug reports or request enhancements.

V A R I A T I O N S

There are two main variants of the DIY cellphone: one that uses a black and white LCD like those found on old

Nokia phones and one that uses an eight-character matrix of red LEDs. The LCD shows more information (six

lines of fourteen characters) but breaks over time. The variant with the LED matrix is harder to use but the display

is more robust.

M A K I N G T H E P H O N E

Making the DIY cellphone can be a fairly involved process but it doesn't necessarily require specific electronics

expertise. You'll need to order the circuit board and electronics components (about $200 total) and have access

to some other electronics tools. There's a good amount of fine hand soldering to be done: about 60 components,

mostly surface-mount, which can take from one to five or ten hours, depending on your experience. Programming

and, especially, debugging the phone can take a while

again, depending on your experience and how muchgoes wrong. Making the case requires some plywood and veneer, along with access to a laser cutter (or you can

find your own way to enclosure the circuit board). In short, this is a difficult but potentially do-able project.

O R D E R I N G T H E C I R C U I T B O A R D

You can order a version of the circuit board fromOSH Park.It costs about $60 and you get three copies of the

board.

OrderLCD variantfrom OSHPark.

OrderLED matrix variantfromOSH Park.

Alternatively, you can upload the Gerber files to a fabrication service yourself, eitherOSH Park,AdvancedCircuits,AP Circuits,or a number of others. Each time I order boards, I save the Gerber files in my GitHub

repository, in a directory named according to the date. Find the latest here: LCD variant,LED matrix variant.

There are a few different files in the directory:

.cmp: top (component) sidecopper layer (i.e. the lines of

copper forming the actual

electronic connections on the top

side of the board)

.sol: bottom (solder) side copperlayer (same, for the bottom of theboard)

.stc: top (component-side) soldermask (stop) layer (i.e. the green

layer covering the copper)

.sts: bottom (solder-side) soldermask (stop) layer

.plc: top (component-side) silkscreen (legend) layer, plus overall

board dimensions (i.e. the white

text on the top of the board, plus a

line indicating the overall board
http://arduino.cc/en/Main/ArduinoGSMShieldhttp://arduino.cc/en/Main/ArduinoGSMShieldhttp://arduino.cc/en/Main/ArduinoGSMShieldhttps://github.com/damellis/cellphone2hwhttps://github.com/damellis/cellphone2hwhttps://github.com/damellis/cellphone2hwhttps://github.com/damellis/cellphone2https://github.com/damellis/cellphone2https://github.com/damellis/cellphone2http://oshpark.com/http://oshpark.com/http://oshpark.com/http://oshpark.com/shared_projects/9KhdfD2Yhttp://oshpark.com/shared_projects/9KhdfD2Yhttp://oshpark.com/shared_projects/9KhdfD2Yhttp://oshpark.com/shared_projects/6Zg0GFONhttp://oshpark.com/shared_projects/6Zg0GFONhttp://oshpark.com/shared_projects/6Zg0GFONhttp://oshpark.com/http://oshpark.com/http://oshpark.com/http://www.4pcb.com/http://www.4pcb.com/http://www.4pcb.com/http://www.4pcb.com/http://www.apcircuits.com/http://www.apcircuits.com/http://www.apcircuits.com/https://github.com/damellis/cellphone2hw/tree/master/Eaglehttps://github.com/damellis/cellphone2hw/tree/master/Eaglehttps://github.com/damellis/cellphone2hw/tree/master/Eaglehttps://github.com/damellis/cellphone2hw/tree/led-matrix/Eaglehttps://github.com/damellis/cellphone2hw/tree/led-matrix/Eaglehttps://github.com/damellis/cellphone2hw/tree/led-matrix/Eaglehttps://github.com/damellis/cellphone2hw/tree/led-matrix/Eaglehttps://github.com/damellis/cellphone2hw/tree/master/Eaglehttp://www.apcircuits.com/http://www.4pcb.com/http://www.4pcb.com/http://oshpark.com/http://oshpark.com/shared_projects/6Zg0GFONhttp://oshpark.com/shared_projects/9KhdfD2Yhttp://oshpark.com/https://github.com/damellis/cellphone2https://github.com/damellis/cellphone2hwhttp://arduino.cc/en/Main/ArduinoGSMShield


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shape for which there isn't a

separate file)

.pls: bottom (solder-side) silkscreen (legend) layer (white text

on the bottom of the board)

.drd: (excellon) drill file (specifieswhere holes should be drilled in

the board and how big they should

be)

.dri: drill tool file, often not needed(text description of the drill sizes

used)

You'll need to upload these (typically in a single zip file) and sometimes specify which file is what. This is a two-

layer board, 5.15" x 2.3", and the standard options for board thickness (0.62"), copper weight (1 oz), and solder

mask should be fine. You'll want to get solder mask and silk-screen on both sides. Getting the corners rounded

might count as a complex shape and cost extra; I think it's worth it but it's not necessary.

G E T T I N G T H E P A R T S

There's no kit available for the cellphone but you can order the parts from various websites.

Electronic Components

Most of the electronic components are available fromSparkFunandDigi-Key.You'll also need to get theM10

GSM Modulefrom the Arduino store.

Bill of Materials:BOM.pdf(LCD variant),BOM.pdf(LED matrix variant)

Tools

To assemble the phone, you'll a need a good soldering setup: a soldering iron (e.g. the WES51)with a good tip,

fine-pitch solder, desolder wick, tweezers, etc. To program the microcontroller, you'll need an AVR in-system

programmer (like theAVRISP mkII)and a3.3V FTDI Cable(or equivalent breakout board). To charge the battery,you'll need a mini-USB cable.

To make the laser-cut case, you'll need access to a laser cutter and a small philips screwdriver.

SIM Card

The phone should work with a full-size SIM card from any GSM provider. I've been using T-Mobile in the United

States but the phone has also been tested with AT&T and in India, China, and Europe.

Other Materials

For the laser cut enclosure, you'll need:

A sheet of 1/4" / 6 mm plywood,like thiscraft plywood from

Midwest Productsavailable at

many art supply stores. (Avoid the

micro-lite aircraft plywood from

Midwest Products or other

plywood with dark adhesive layers

as they tend to burn in the laser-

cutter.)

A sheet of wood veneer,preferably with adhesive backing.
http://www.sparkfun.com/http://www.sparkfun.com/http://www.sparkfun.com/http://www.digikey.com/http://www.digikey.com/http://www.digikey.com/http://store.arduino.cc/ww/index.php?main_page=product_info&cPath=6_33&products_id=289http://store.arduino.cc/ww/index.php?main_page=product_info&cPath=6_33&products_id=289http://store.arduino.cc/ww/index.php?main_page=product_info&cPath=6_33&products_id=289http://store.arduino.cc/ww/index.php?main_page=product_info&cPath=6_33&products_id=289https://github.com/damellis/cellphone2hw/blob/master/Components/BOM.pdf?raw=truehttps://github.com/damellis/cellphone2hw/blob/master/Components/BOM.pdf?raw=truehttps://github.com/damellis/cellphone2hw/blob/master/Components/BOM.pdf?raw=truehttps://github.com/damellis/cellphone2hw/blob/led-matrix/Components/BOM.pdf?raw=truehttps://github.com/damellis/cellphone2hw/blob/led-matrix/Components/BOM.pdf?raw=truehttps://github.com/damellis/cellphone2hw/blob/led-matrix/Components/BOM.pdf?raw=truehttp://www.digikey.com/product-detail/en/WES51/WES51-120V-ND/526397http://www.digikey.com/product-detail/en/WES51/WES51-120V-ND/526397http://www.digikey.com/product-detail/en/WES51/WES51-120V-ND/526397http://www.digikey.com/product-detail/en/ATAVRISP2/ATAVRISP2-ND/898891http://www.digikey.com/product-detail/en/ATAVRISP2/ATAVRISP2-ND/898891http://www.digikey.com/product-detail/en/ATAVRISP2/ATAVRISP2-ND/898891http://www.digikey.com/product-detail/en/TTL-232R-3V3/768-1015-ND/1836393http://www.digikey.com/product-detail/en/TTL-232R-3V3/768-1015-ND/1836393http://www.digikey.com/product-detail/en/TTL-232R-3V3/768-1015-ND/1836393http://www.midwestproducts.com/store/product/3282e69c-13f4-452f-9906-a40c0a5a9d8a/6mm_14_x_12_x_12_Craft_Plywood.aspxhttp://www.midwestproducts.com/store/product/3282e69c-13f4-452f-9906-a40c0a5a9d8a/6mm_14_x_12_x_12_Craft_Plywood.aspxhttp://www.midwestproducts.com/store/product/3282e69c-13f4-452f-9906-a40c0a5a9d8a/6mm_14_x_12_x_12_Craft_Plywood.aspxhttp://www.midwestproducts.com/store/product/3282e69c-13f4-452f-9906-a40c0a5a9d8a/6mm_14_x_12_x_12_Craft_Plywood.aspxhttp://www.midwestproducts.com/store/product/3282e69c-13f4-452f-9906-a40c0a5a9d8a/6mm_14_x_12_x_12_Craft_Plywood.aspxhttp://www.midwestproducts.com/store/product/3282e69c-13f4-452f-9906-a40c0a5a9d8a/6mm_14_x_12_x_12_Craft_Plywood.aspxhttp://www.digikey.com/product-detail/en/TTL-232R-3V3/768-1015-ND/1836393http://www.digikey.com/product-detail/en/ATAVRISP2/ATAVRISP2-ND/898891http://www.digikey.com/product-detail/en/WES51/WES51-120V-ND/526397https://github.com/damellis/cellphone2hw/blob/led-matrix/Components/BOM.pdf?raw=truehttps://github.com/damellis/cellphone2hw/blob/master/Components/BOM.pdf?raw=truehttp://store.arduino.cc/ww/index.php?main_page=product_info&cPath=6_33&products_id=289http://store.arduino.cc/ww/index.php?main_page=product_info&cPath=6_33&products_id=289http://www.digikey.com/http://www.sparkfun.com/


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Six M0, 5/8", pan-head machinescrews (e.g. this100 pack from

McMaster-Carr)

Six M0 nuts (e.g. this50 packfrom McMaster-Carr)

Or, try making a difference enclosure (e.g. with 3D-printing or by milling a mold).

Images of the assembled circuit boards (LCD variant). Click to enlarge.

Images of the assembled circuit boards (LED matrix variant). Click to enlarge.

S O L D E R I N G T H E E L E C T R O N I C S

While the cellphone uses many small, surface-mount components, it's possible to solder it together by hand with

a good soldering iron and some practice. Most of the components are straightforward to solder (apart from their

small size), with a few exceptions:

Capacitors: Be careful of thepolarity on the large (1000 uF)

capacitors, they may explode if

you solder them backwards. Use

the orange stripe to orient themcorrectly.

Polarity: Other components withpolarity include the super-

capacitor, the LEDs (note the two

small green dots on one side), the

ATmega1284P microcontroller

(note the circle in one corner), the

M10 GSM module (which has an

arrow in one corner), the SIM card

socket, the microphone, and the

diode (note the faint grey line onone side). These components
http://www.mcmaster.com/#91772A060http://www.mcmaster.com/#91772A060http://www.mcmaster.com/#91772A060http://www.mcmaster.com/#91772A060http://www.mcmaster.com/#90730A001http://www.mcmaster.com/#90730A001http://www.mcmaster.com/#90730A001http://www.mcmaster.com/#90730A001http://www.flickr.com/photos/mellis/9162546146/http://www.flickr.com/photos/mellis/9160323897/http://www.flickr.com/photos/mellis/8383433747/http://www.flickr.com/photos/mellis/8384518274/http://www.flickr.com/photos/mellis/9162546146/http://www.flickr.com/photos/mellis/9160323897/http://www.flickr.com/photos/mellis/8383433747/http://www.flickr.com/photos/mellis/8384518274/http://www.flickr.com/photos/mellis/9162546146/http://www.flickr.com/photos/mellis/9160323897/http://www.flickr.com/photos/mellis/8383433747/http://www.flickr.com/photos/mellis/8384518274/http://www.flickr.com/photos/mellis/9162546146/http://www.flickr.com/photos/mellis/9160323897/http://www.flickr.com/photos/mellis/8383433747/http://www.flickr.com/photos/mellis/8384518274/http://www.mcmaster.com/#90730A001http://www.mcmaster.com/#90730A001http://www.mcmaster.com/#91772A060http://www.mcmaster.com/#91772A060


12/20

have no polarity (can be soldered

either way around): the crystal (8

MHz), speaker, reset button, small

capacitors, and resistors. Other

components only physically align

in one orientation (but make surethe transistors aren't upside down

and that the buttons aren't rotated

90 degrees).

Antenna: When soldering theantenna, start with the pad that

faces the GSM module. That's the

one that carries the electrical

signal; the others are simply there

for structural support (to hold the

antenna down). You may even be

able to heat the solder on that padfrom the top of the antenna, the

heat can be conducted through

the two vias (small holes) in it.

Solder Jumpers: There are twosolder jumpers on the bottom of

the board, labelled "Cell" and

"uC". Solder the center pad of

each to the pad labelled "uC".

(This connects the RX and TX

lines from the FTDI header to the

ATmega1284P on the board sothat they communicate over serial.

If you instead solder the center

pad to the "Cell" pad, the FTDI

cable connects directly to the

GSM module so that you can

communicate with it from the

computer.)

Speaker: The speaker is awkwardto solder because it has no legs.

First, apply solder to the pads on

the PCB. Then rest the speakeron top of the PCB (aligning its

pads with those on the board) and

solder it from the bottom. You can

feed in solder or melt the pre-

applied solder from below. If it

doesn't work, don't remove the

speaker(you might rip its pads

off). Instead, try to re-melt the

solder on its pads by inserting the

iron into the holes from below.

USB Connector: Only the twoouter (of the five small) legs of the


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USB connector are used, so you

don't have to solder the three

central legs. (Do solder the four

corners, though, they provide

structural support).

ISP Header: Because you onlyneed to burn the bootloader once,

I typically don't solder pins into the

ISP (2x3) header. Instead, you

can insert pins into the connector

on your ISP and hold them

against the pins (from the top of

the board) while you burn the

bootloader. If you have trouble,

you can solder pins to the holes

but you'll have to adjust the case

to make room for it. LCD(LCD variant only): You only

need to solder the eight pins at

the top of the screen, not the eight

pins on the bottom. To solder

them, insert male header pins

from the bottom (so that their

plastic portion is under the board).

First solder them to the PCB, then

put the display on top (verifying its

orientation). Then solder the pins

to the display.C O M P I L I N G T H E S O F T W A R E

The cellphone's software is an Arduino program that makes use of various libraries and a third-party hardware

definition. You can compile and upload it with the Arduino software but some initial setup is required:

1. Download and install Arduino1.0.4 (tested) or 1.0.5 from

theArduino software page.

2. Install theGit version controlsoftware.See, for example, the

instructions from GitHub

forWindowsorMac.3. Checkout the cellphone's source

codefrom GitHub,e.g. "git clone

https://github.com/damellis/cellpho

ne2.git". Then "cd cellphone2" to

change into the source code's

directory.

4. Checkout the other repositoriesused by the cellphone's software

with "git submodule init" and "git

submodule update".

5. For the LED matrix variant,checkout the LED matrix branch
http://arduino.cc/en/Main/Softwarehttp://arduino.cc/en/Main/Softwarehttp://arduino.cc/en/Main/Softwarehttp://git-scm.com/http://git-scm.com/http://git-scm.com/http://git-scm.com/https://help.github.com/articles/set-up-git#platform-windowshttps://help.github.com/articles/set-up-git#platform-windowshttps://help.github.com/articles/set-up-git#platform-windowshttps://help.github.com/articles/set-up-git#platform-machttps://help.github.com/articles/set-up-git#platform-machttps://help.github.com/articles/set-up-git#platform-machttps://github.com/damellis/cellphone2https://github.com/damellis/cellphone2https://github.com/damellis/cellphone2https://github.com/damellis/cellphone2https://help.github.com/articles/set-up-git#platform-machttps://help.github.com/articles/set-up-git#platform-windowshttp://git-scm.com/http://git-scm.com/http://arduino.cc/en/Main/Software


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with "git checkout led-matrix".

(The code for the LCD variant is

stored in the default master

branch.)

6. Run Arduino and, in thepreferences dialog, set yoursketchbook folder to the

cellphone2 directory (that you

checked out from github).

7. Also in the preferences dialog,enable verbose information on

compile and upload. (This will help

you debug if anything goes

wrong.)

8. Restart the Arduino software.9. Select "DIY Cellphone" from the

Tools > Board menu.10. Select AVRISP mkII (or whichever

programmer you're using) from

the Tools > Programmer menu.

11. Plug the LiPo battery into thecellphone.

12. Initiate "Burn Bootloader" from theTools menu (while holding the

pins in the ISP header against the

corresponding holes in the PCB).

This may take a few minutes.

13. Connect the 3.3V FTDI cable tothe FTDI header (the black wire

goes on the side labelled "B", the

green on the side labelled "G").

14. Open the Cellphone sketch fromthe sketchbook.

15. From the Tools > Serial Portmenu, select the item

corresponding to the FTDI cable.

16. Upload the Cellphone sketch.17. The screen should turn on and

show the word "connecting".18. Insert a SIM card into the socket.19. It may take a while for the

cellphone to connect to the

network. If it doesn't connect after

a few minutes, try resetting the

board (by pressing the small reset

button). You can see debugging

information in the Arduino serial

monitor at 9600 baud.

20. Once the phone connects to thenetwork, you'll see the words"connected" and "caching" on the


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screen. After a few seconds, the

screen will go blank. That's a sign

that the phone has successfully

started up and is now on the lock

screen. See "using the phone"

below for more information.5/23/13 15:54

unlock

The unlocking screen (backlight will be off)

5/23/13 15:54

lock menu

The home screen

617

back call

The dialing screen

U S I N G T H E P H O N E

Unlocking the Phone

Once the phone successfully starts up, it will be locked and the screen will be blank. To unlock the phone, press

any button; the date and time will appear on the screen for a few seconds (this is the "unlocking" screen). On the

LED matrix variant, the date and time will scroll back and forth across the screen. If, during this time, you press

the "unlock" key (the top-left button), the phone will unlock and, if using the LCD variant, the screen's backlight

will turn on. On the LCD variant, the date and time will remain on-screen, and the soft-keys labels will read "lock"

and "menu". On the LED matrix variant, the time will remain on the display, without scrolling. This is the home

screen.

Locking the Phone

From the home screen, you can lock the phone by pressing the left soft-key button (the upper-left button). The

screen and backlight will turn off but the phone will still be on and able to receive phone calls or text messages.

Adjusting the Contrast/Brightness

When the phone is in the "unlocking" screen, you can adjust the contrast (for the LCD variant) or brightness (for

the LED matrix variant) by using the up and down buttons (the two central buttons of the group of four buttons

just below the screen).

Dialing a Phone Number

You can dial a number from the home screen. Simply press the button corresponding to the first digit of the

number. You'll be taken to the dialing screen where you can enter the rest of the number. Press * to delete the

last digit entered or "back" (the left soft-key) to go back to the home screen. By pressing # one or more times in

succession, you can enter #, *, or +. To call the number, press the right soft-key ("call").


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Using the Phone Book (Contact List)

From the home screen, press the down arrow (the lower of the group of four buttons just below the display) to

enter the phone book. Use the down and up arrows to navigate to the desired entry. Press the right soft-key

("okay") to enter a menu from which you can call that contact, send a text message to that contact, add a new

entry to the address book, or edit or delete the contact.

Adding a Contact

To add a contact, first enter the contact list by pressing the down arrow from the home screen. Then press the

right button to enter the contact menu ("call", "text", "add entry", etc); scroll (using the down and up buttons) down

to the "add entry" menu item and press the right button. Now you can enter the name of the contact using the

keypad (2 is "abc", 3 is "def", etc.; 1 is space, * is backspace, and # is shift). Once you've entered the contact's

name, press the down arrow to move to the field for entering the contact's phone number. (You can press the up

arrow to return to the field for entering the contact's name.) Enter the contact's number using the keypad (* is

again backspace, but # now cycles between #, *, and +). When you've entered both the name and phone

number, press the right button to save the contact (or the left button to cancel).

Calling a ContactTo call a contact in your contact list, scroll to that contact, press the right button to bring up the contact menu

("call", "text, etc.) and then press the right button again to call.

Texting a Contact

To text a contact, scroll to their entry in your contact list and press the right button to bring up the contact menu.

Scroll down to "text" and press the right button. Now you can enter your message using the keypad. (As for

entering a contact's name, 2 is "abc", 3 is "def", etc.; 1 is space, * is backspace, and # is shift.) Press the right

button to send the text (or the left button to cancel).

T R O U B L E S H O O T I N G

There are a lot of pieces and, therefore, a lot of things that might not work. Here are some potential problems andsome possible solutions.

Can't burn the bootloader onto the microcontroller.

Does the microcontroller havepower? (Is the battery is plugged

in and charged?)

Are the legs of the microcontrollersoldered correctly (i.e. is each leg

actually soldered to the

corresponding pad and are the

legs free of shorts / solderbridges)? In particular, check the

legs connected to the ISP header,

to VCC, and to ground.

Are the pins in the header of theISP being held firmly against the

corresponding holes on the

board? You might try soldering

pins into the ISP header (on top of

the board).

Is the crystal soldered correctly?(If not, the first step of burning the


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bootloader might succeed but the

second one might fail.)

Can't compile the cellphone program.

Are you using Arduino 1.0.4 or1.0.5?

Did you checkout the submodulesof the cellphone2 repository?

(They contain the required

libraries and board definition.)

Is the Arduino sketchbook folderset to the cellphone2 folder?

(Otherwise, the Arduino software

won't be able to find the libraries

and the board definition.)

Is "DIY Cellphone" selected fromthe Tools > Board menu?

Can't upload the cellphone program. Is the FTDI cable connected

correctly (black wire to side

labelled "B"; green wire to "G")?

Did you select the right serial portfrom the Tools > Serial Port

menu? (Try unplugging the FTDI

cable and see which item

disappears from the menu; that's

the one corresponding to the

cable.)

Are the solder jumpers solderedcorrectly (central pad connected

to the "uC" pad)?

Is the board powered? Is the FTDI header soldered

correctly? The 0.1 uF capacitors

near it? The RX and TX legs of

the microcontroller?

Is the crystal still solderedcorrectly?

Did the bootloader burnsuccessfully? (If not, see thatissue above.)

Can't connect to the network.

Is there a SIM card in the socket? Is the SIM socket soldered

correctly? The 22 ohm resistors?

The corresponding pads on the

GSM module?

Is the antenna soldered correctly?The corresponding pad on the

GSM module?

Is the 0 ohm resistor solderedcorrectly (to the trace connecting


18/20

the M10 GSM module to the

antenna)?

Do you have reception? Is the SIM card locked to another

phone?

AT&T (and possibly othercarriers): have you activated your

SIM card and phone on AT&T's

website? You'll need the IMEI

number printed on the M10 GSM

module.

Another component doesn't work (e.g. display, speaker, microphone, buzzer).

Is the component solderedcorrectly?

Are the connected components(e.g. the corresponding legs of the

microcontroller or GSM module)soldered correctly?

S E R I A L D E B U G G I N G

You can further debug the phone by communicating with the GSM module via serial communication with the

computer, using the microcontroller as a proxy. To do so, upload the SerialProxy sketch to the phone (using a

3.3V FTDI cable or breakout board). Then open the serial monitor and set the baud rate to 9600 and the line

ending to "carriage return". After a few seconds, you should see:

READY

AT

OK

That means the GSM is ready to receive AT commands (text strings that mostly start with the letters "AT"). The

commands are detailed in thedatasheet for the GSM modulebut here are a few basic ones:

AT

Test/synchronization

command. If you enter "AT"

in the serial monitor (with a

"carriage return" line

ending), you should get a

response of "OK".

AT+CREG?

Check the status of thenetwork registration

(connection). The response

will be in the form "+CREG

0,N", with N being: 0 (not

registered to a network), 1

(registered to a network), 2

(searching for networks), 3

(network registration

denied), or 5 (registered,

roaming).

AT+CPBS?
http://arduino.cc/en/uploads/Main/Quectel_M10_AT_commands.pdfhttp://arduino.cc/en/uploads/Main/Quectel_M10_AT_commands.pdfhttp://arduino.cc/en/uploads/Main/Quectel_M10_AT_commands.pdfhttp://arduino.cc/en/uploads/Main/Quectel_M10_AT_commands.pdf


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Display currently-selected

phone book. Sample

response: "+CPBS:

"SM",50,250", with the "SM"

indicating the SIM card is

the current phone book(some other options include

"MC" for the missed call list,

"RC" for the received call

list, and "ME" for the GSM

module phone-book) and

that 50 of its 250 entries are

in use. This command can

be useful for verifying that

the GSM module is able to

communicate with the SIM

card.

AT+CPBS="SM"

Select the SIM card's phone

book. You can also replace

the "SM" with the

abbreviations for the other

phone books listed

previously.

AT+CPBR=1

Read the first entry from thecurrently-selected phone

book. Replace the 1 with the

number of the entry you

wish to read (up to the total

phone book size reported by

AT+CPBS?).

M A K I N G T H E E N C L O S U R E

You can make a simple but functional enclosure from laser-cut plywood and veneer, along with some small

screws (see materials above):

1. Before cutting the case, checkthat the case files match the

circuit board. In particular, I've

made a lot of tweaks to the size

and location of the screw holes,

so check that they're in the same

place on the PCB and the case.

(Note that the holes in the bottom

veneer file should be bigger than

the others, this is to accommodate

the nut, recessing it slightly.)


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2. If you soldered pins onto the ISPheader, you'll need to cutout a

space for them in the top piece of

plywood. Edit DIY-Cellphone-Top

accordingly.

3. Laser-cut the plywood (1/4" /6mm) using the DIY-Cellphone-

Top and DIY-Cellphone-Bottom

files in theCase/ folderof the

damellis/cellphone2hw repository

on GitHub. The SVG files were

created in Inkscape, then

exported to hpgl for importing to

CorelDraw.

4. Laser-cut the veneer using theDIY-Cellphone-Top-Veneer and

DIY-Cellphone-Bottom-Veneerfiles. Cut the veneer with the wood

front facing up (adhesive back

face down).

5. Remove the adhesive backingfrom the top veneer piece and

stick it to the outer face of the top

plywood piece. Repeat with the

back, again attaching the veneer

to the outer face of the plywood.

6. There's a bit of empty spacebetween the top of each buttonand the veneer. You might need

to stick small spacers to the back

of the top piece of veneer, one for

each button (in the middle of each

rectangular flexure cutout in the

veneer). That way, you don't have

to depress the veneer as much to

press the button.

7. Slip the top and bottom pieces ofthe case over the circuit board.

You'll have to fit the battery's wirein between the GSM module and

the battery connector, folding it in

half. The plywood pieces should

rest flat against the circuit board.

8. Insert the six screws and threadthem onto the nuts.
https://github.com/damellis/cellphone2hw/tree/master/Casehttps://github.com/damellis/cellphone2hw/tree/master/Casehttps://github.com/damellis/cellphone2hw/tree/master/Casehttps://github.com/damellis/cellphone2hw/tree/master/Case