DT2 Projekt-3: Baud Rate Generator & GPS Decoder

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School of Engineerin g DT2 Projekt-3: Baud Rate Generator & GPS Decoder

description

DT2 Projekt-3: Baud Rate Generator & GPS Decoder. GPS Uhr Überblick. GPS Uhr Minimum Features. GPS Decoder. Uart-RX Unit. from GPS RX module. (gegeben). LCD Controller (Loader). LCD Driver. to LCD Display. MaxII CPLD. Sample Punkte des UART. UART RX. Signal abtasten - PowerPoint PPT Presentation

Transcript of DT2 Projekt-3: Baud Rate Generator & GPS Decoder

School ofEngineering

DT2 Projekt-3:Baud Rate Generator & GPS Decoder

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GPS Uhr Überblick

UARTRX

Infra-struktur

GPSReceiver

GPSDecoder

DisplayDriver

Display

DebugI/O

50MHzOszillator

CPLD

LED

MAXII Board

Reset

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GPS Uhr Minimum Features

Uart-RXUnit

GPSDecoder

LCDController(Loader)

LCDDriver

MaxII CPLD

from GPSRXmodule

to LCDDisplay

(gegeben)

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Sample Punkte des UART

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serial_in

UART RX

rx_data(7:0)

rx_data_valid

Signal abtasten

Edge erkennen(Start Bits)

Tick für Abtastung generieren

Data Bits abtasten

Daten Buffer 1 Byte Neues Byte an Decoder melden

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Abtasten des seriellen Datenstroms

P

edge

TT + ½ T

baud_tick

0 1 2 3 4 5 6 7Bit-Pointer

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serial_in

UART RX

rx_data(7:0)

EdgeDetector

clock

reset

TickGenerator

Daten Buffer

Steuerung

rx_data_valid

School ofEngineeringBaud Rate Generator

Tick Generator

BaudRate

Generator

50MHz

Edge

Reset Baud_tick

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Taktteiler-Baud Rate Generator

LoadValue

LoadValue -1

LoadValue -2 0

50MHz

Edge

Baud Counter

Baud_tick

ReloadValue 0

1/4800s1.5/4800 s

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uart_rx_out

rx_data(7:0)rx_data_valid

GPS Decoder

gps_time

sec_einer(7:0)sec_zehner(7:0)min_einer(7:0)min_zehner(7:0)std_einer(7:0)std_zehner(7:0)

Nach dem GPS Telegramm Headersuchen

Nur die Bytes mit der Zeitinformation abspeichern

Zeitinformation an den Display Controllerweitergeben

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GPS Telegram

Link: http://www.kowoma.de/gps/index.htmNMEA-0183 Protokoll : http://www.kowoma.de/gps/zusatzerklaerungen/NMEA.htm

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ASCII Zeichensatz

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idle

5

2

1

0

,

G

P

P

$

!V

!V

!V

!V

!V

!Valid

V

V

V

V

V“$“

V & “G“

V & “P“

V & “G“

V & “,“

V & ! “$“

V & ! G

GPS Decoder Statemachine

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GPSDecoder

0

1

2

3

4

5

UART_DATA

sec_einer

sec_zehner

min_einer

min_zehner

std_einer

std_zehner

CLK

VALID

Time Register

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LCD Driver

(gegeben)

CLK

CHAR_NUM

DIN

WEN

LCD_DATA

LCD_RS

LCD_RW

LCD_E

8 LCDDRIVER LCD

DISPLAY7

LCDController

Loader

sec_einer

sec_zehner

min_einer

min_zehner

std_einer

std_zehner

RESET

CLK

RESET

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Schnittstelle: LCD-Driver to LCD-Display

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Schnittstelle: LCD-Loader to LCD-Driver

50MHz

Char_num

WEN

0 1 2 3

X”41” X”42” X”43” X”44”DIN

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BaudeRate

Generator

Pointer

LCDDriver

sec_einer

CLK

DIN

char_num7

8

Baud_tick

WEN

LCD – Controller (Loader)

sec_zehner

min_einer

min_zehner

std_einer

std_zehner

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BaudeRate

Generator

Pointer

LCDDriver

x “41“x “42“x “43“x “44“x “45“x “46“

CLK

DIN

char_num7

8

Baud_tick

WEN

LCD – Controller (Loader)