[avr] add DOW CRC8 function and add the checksum to a ctrl message

This commit is contained in:
Bart Van Der Meerssche 2011-01-15 23:03:16 +01:00
parent 968e25c863
commit f74b124884
2 changed files with 23 additions and 1 deletions

View File

@ -20,6 +20,7 @@
// $Id$
#include <avr/eeprom.h>
#include <util/crc16.h>
#include "global.h"
#include "main.h"
@ -204,9 +205,19 @@ void ctrlRxToTxLoop(void)
}
}
uint8_t ctrlCalcCrc8(cBuffer* buffer)
{
uint8_t i, crc = 0;
for (i = 0; i < buffer->datalength; i++) {
crc = _crc_ibutton_update(crc, bufferGetAtIndex(buffer, i));
}
return crc;
}
void ctrlDecode(void)
{
uint8_t cmd[2];
uint8_t cmd[2], crc;
ctrlFlushTxBuffer();
@ -231,6 +242,9 @@ void ctrlDecode(void)
ctrlAddToTxBuffer('z');
}
crc = ctrlCalcCrc8(&ctrlTxBuffer);
ctrlWriteCharToTxBuffer(crc);
ctrlAddToTxBuffer('.');
}

View File

@ -104,6 +104,14 @@ void ctrlFlushTxBuffer(void);
*/
void ctrlRxToTxLoop(void);
/**
* Calculate the CRC-8 checksum over the bytes in the buffer.
*
* @param buffer pointer to the buffer containing the data
* @return CRC-8 checksum
*/
uint8_t ctrlCalcCrc8(cBuffer* buffer);
/**
* Decode the message in the ctrl Rx buffer and dispatch to either ctrlCmdGet,
* ctrlCmdSet or ctrlCmdCommit.