Mam malutki problem z implementacja protokolu komunikacji radia ze zmieniarka....
Ale od poczatku:
Znam interwaly impulsow generalnie caly protokol jest opisany.
Quote:
There are three different bit identifiers
Start bit: It consists of a 9ms high phase followed by a 4.5ms low phase.
0-Bit: A bit with a value of 0, is represented by an equal-long high and low phase. The length is in each case 0.55 ms. The bit thus has a total length of 1.1 ms.
1 bit: A bit with a value of 1, represents a 0.55 ms long high pulse followed by a 1.7 ms low phase. The total length is therefore 2.25 ms.
A command consists of 4 bytes, whereby in my interpretation the LSB (least significant bit) of each byte is sent first.
1st byte: always CA hex.
2nd byte: always 34 hex.
3. Byte: The command which is evaluated.
4. Byte: Again the command with inverted bit.
The bit sequence "01010011 00101100 01111000 10000111" can be seen in the figure above. This corresponds to the hexadecimal representation "CA 34 1e e1". In this case, the radio has indicated that the next track should be played.
Posiadam rowniez kod napisany na Atmega8 ale niestety jest nie kompatybilny z Atmega328 albo ja cos robie zle ...
[syntax=c]/*
* VAG_CDC.c
*
* Created: 23.06.2013 20:00:51
* Author: Dennis Schuett, dev.shyd.de
*/
#define F_CPU 8000000UL
#include <inttypes.h>
#include <avr/io.h>
#include <avr/interrupt.h>
#include <util/delay.h>
#include "uart.h"
#define UART_BAUD_RATE 9600
#define LED_PWR PA0
#define RADIO_OUT PD2
#define FT_CBUS1 PD3
#define RADIO_OUT_IS_HIGH (PIND & (1<<RADIO_OUT))
#define CDC_PREFIX1 0x53
#define CDC_PREFIX2 0x2C
#define CDC_END_CMD 0x14
#define CDC_PLAY 0xE4
#define CDC_STOP 0x10
#define CDC_NEXT 0xF8
#define CDC_PREV 0x78
#define CDC_SEEK_FWD 0xD8
#define CDC_SEEK_RWD 0x58
#define CDC_CD1 0x0C
#define CDC_CD2 0x8C
#define CDC_CD3 0x4C
#define CDC_CD4 0xCC
#define CDC_CD5 0x2C
#define CDC_CD6 0xAC
#define CDC_SCAN 0xA0
#define CDC_SFL 0x60
#define CDC_PLAY_NORMAL 0x08
#define MODE_PLAY 0xFF
#define MODE_SHFFL 0x55
#define MODE_SCAN 0x00
uint16_t captimehi = 0;
uint16_t captimelo = 0;
uint8_t capturingstart = 0;
uint8_t capturingbytes = 0;
uint32_t cmd = 0;
uint8_t cmdbit = 0;
uint8_t newcmd = 0;
uint8_t shutdownpending = 0;
uint8_t getCommand(uint32_t cmd);
void shutdown();
void softreset();
volatile uint8_t cd;
volatile uint8_t tr;
volatile uint8_t mode;
ISR(INT0_vect) //remote signals
{
if(RADIO_OUT_IS_HIGH)
{
if (capturingstart || capturingbytes)
{
captimelo = TCNT1;
}
else
capturingstart = 1;
TCNT1 = 0;
//eval times
if (captimehi > 8300 && captimelo > 3500)
{
capturingstart = 0;
capturingbytes = 1;
//uart_puts("startseq found\r\n");
}
else if(capturingbytes && captimelo > 1500)
{
//uart_puts("bit 1\r\n");
cmd = (cmd<<1) | 0x00000001;
cmdbit++;
}
else if (capturingbytes && captimelo > 500)
{
//uart_puts("bit 0\r\n");
cmd = (cmd<<1);
cmdbit++;
}
else
{
//uart_puts("nothing found\r\n");
}
if(cmdbit == 32)
{
//uart_puts("new cmd\r\n");
newcmd = 1;
cmdbit = 0;
capturingbytes = 0;
}
}
else
{
captimehi = TCNT1;
TCNT1 = 0;
}
}
int main(void)
{
cd = 0xBE;
tr = 0xFF;
mode = 0xFF;
//LEDs
//pullup
uart_init(UART_BAUD_SELECT(UART_BAUD_RATE, F_CPU));
TCCR1B |= (1<<CS11); // no prescaler 8 -> 1 timer clock tick is 1us long
GICR |= (1<<INT0) | (1<<INT1);
MCUCR |= (1<<ISC00) | (1<<ISC10); //any change on INT0 and INT1
sei();
//init led on
_delay_ms(500);
//uart_puts("VAG_CDC ready...\r\n");
uart_putc(0xAA);
uart_putc(0x55);
while(1)
{
int r = uart_getc();
//r has new data
if(r <= 0xFF)
{
//send inverted CD No.
if((r & 0xC0) == 0xC0)
{
if (r == 0xCA)
mode = MODE_SCAN;
else if (r == 0xCB)
mode = MODE_SHFFL;
else if (r == 0xCC)
mode = MODE_PLAY;
else
cd = 0xFF^(r & 0x0F);
}
//send inverted TR No.
else
tr = 0xFF^r;
}
_delay_ms(41);
if (newcmd)
{
newcmd = 0;
uint8_t c = getCommand(cmd);
if (c)
{
uart_putc(c);
}
}
}
}
uint8_t getCommand(uint32_t cmd)
{
if (((cmd>>24) & 0xFF) == CDC_PREFIX1 && ((cmd>>16) & 0xFF) == CDC_PREFIX2)
if (((cmd>>8) & 0xFF) == (0xFF^((cmd) & 0xFF)))
return (cmd>>8) & 0xFF;
return 0;
}[/syntax]
Generalnie nie potrzebuje poprawienia spi wysylki i odbierania bo to juz mam i dziala poprawnie bardzie martwi mnie ISR(INT0_vect) oraz deklaracje rejestrow/Timerow.
Moja wiedza na temat C w AVR jest slaba ale ciagle czytam i sie szkole ale na tym poleglem nie potrafie tego sportowac, lub napisac od zera.
Przepraszam za brak pl znaczkow.
Dziekuje za kazda informacje, naprowadzenie na wlasciwy trop.
Pozdrawiam
Piotr
P.S.
Panie Mirku dzieki za EclipsaStatystyki: Napisane przez Moriusz — 23 kwi 2017, o 21:37
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