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CHG: extracted some timers functionality, to get unified access to a timer/clock which counts in ticks. Moved stuff from util.c

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This commit is contained in:
iceman1001 2016-09-21 19:03:32 +02:00
commit 22f4dca88c
10 changed files with 372 additions and 274 deletions
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26
common/crc.c
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@ -43,6 +43,8 @@ void crc_update(crc_t *crc, uint32_t indata, int data_width){
crc->state ^= indata << (crc->order - data_width);
for( uint8_t bit = data_width; bit > 0; --bit) {
// Try to divide the current data bit.
if (crc->state & crc->topbit)
crc->state = (crc->state << 1) ^ crc->polynom;
@ -51,6 +53,22 @@ void crc_update(crc_t *crc, uint32_t indata, int data_width){
}
}
void crc_update2(crc_t *crc, uint32_t data, int data_width)
{
if (crc->refin) data = reflect(data, data_width);
int i;
for(i=0; i<data_width; i++) {
int oldstate = crc->state;
crc->state = crc->state >> 1;
if( (oldstate^data) & 1 ) {
crc->state ^= crc->polynom;
}
data >>= 1;
}
}
uint32_t crc_finish(crc_t *crc) {
uint32_t val = crc->state;
if (crc->refout) val = reflect(val, crc->order);
@ -83,6 +101,14 @@ uint32_t CRC8Maxim(uint8_t *buff, size_t size) {
}
// width=4 poly=0xC, reversed poly=0x7 init=0x5 refin=true refout=true xorout=0x0000 check= name="CRC-4/LEGIC"
uint32_t CRC4Legic(uint8_t *cmd, size_t size) {
crc_t crc;
crc_init_ref(&crc, 4, 0x19 >> 1, 0x5, 0, TRUE, TRUE);
crc_update2(&crc, 1, 1); /* CMD_READ */
crc_update2(&crc, cmd[0], 8);
crc_update2(&crc, cmd[1], 8);
return reflect(crc_finish(&crc), 4);
}
// width=8 poly=0x63, reversed poly=0x8D init=0x55 refin=true refout=true xorout=0x0000 check=0xC6 name="CRC-8/LEGIC"
// the CRC needs to be reversed before returned.
uint32_t CRC8Legic(uint8_t *buff, size_t size) {

1
common/crc.h
View file

@ -44,6 +44,7 @@ extern void crc_init(crc_t *crc, int order, uint32_t polynom, uint32_t initial_v
* data_width lower-most bits are used).
*/
extern void crc_update(crc_t *crc, uint32_t data, int data_width);
extern void crc_update2(crc_t *crc, uint32_t data, int data_width);
/* Clean the crc state, e.g. reset it to initial_value */
extern void crc_clear(crc_t *crc);