mirror of
https://github.com/DarkFlippers/unleashed-firmware
synced 2024-12-19 01:03:22 +00:00
64 lines
2.4 KiB
C
64 lines
2.4 KiB
C
|
/* Citroen TPMS. Usually 443.92 Mhz FSK.
|
||
|
|
*
|
||
|
|
* Preamble of ~14 high/low 52 us pulses
|
||
|
|
* Sync of high 100us pulse then 50us low
|
||
|
|
* Then Manchester bits, 10 bytes total.
|
||
|
|
* Simple XOR checksum. */
|
||
|
|
|
||
|
|
#include "../../app.h"
|
||
|
|
|
||
|
|
static bool decode(uint8_t *bits, uint32_t numbytes, uint32_t numbits, ProtoViewMsgInfo *info) {
|
||
|
|
|
||
|
|
/* We consider a preamble of 17 symbols. They are more, but the decoding
|
||
|
|
* is more likely to happen if we don't pretend to receive from the
|
||
|
|
* very start of the message. */
|
||
|
|
uint32_t sync_len = 17;
|
||
|
|
const char *sync_pattern = "10101010101010110";
|
||
|
|
if (numbits-sync_len < 8*10) return false; /* Expect 10 bytes. */
|
||
|
|
|
||
|
|
uint64_t off = bitmap_seek_bits(bits,numbytes,0,numbits,sync_pattern);
|
||
|
|
if (off == BITMAP_SEEK_NOT_FOUND) return false;
|
||
|
|
FURI_LOG_E(TAG, "Renault TPMS preamble+sync found");
|
||
|
|
|
||
|
|
info->start_off = off;
|
||
|
|
off += sync_len; /* Skip preamble + sync. */
|
||
|
|
|
||
|
|
uint8_t raw[10];
|
||
|
|
uint32_t decoded =
|
||
|
|
convert_from_line_code(raw,sizeof(raw),bits,numbytes,off,
|
||
|
|
"01","10"); /* Manchester. */
|
||
|
|
FURI_LOG_E(TAG, "Citroen TPMS decoded bits: %lu", decoded);
|
||
|
|
|
||
|
|
if (decoded < 8*10) return false; /* Require the full 10 bytes. */
|
||
|
|
|
||
|
|
/* Check the CRC. It's a simple XOR of bytes 1-9, the first byte
|
||
|
|
* is not included. The meaning of the first byte is unknown and
|
||
|
|
* we don't display it. */
|
||
|
|
uint8_t crc = 0;
|
||
|
|
for (int j = 1; j < 10; j++) crc ^= raw[j];
|
||
|
|
if (crc != 0) return false; /* Require sane checksum. */
|
||
|
|
|
||
|
|
info->pulses_count = (off+8*10*2) - info->start_off;
|
||
|
|
|
||
|
|
int repeat = raw[5] & 0xf;
|
||
|
|
float kpa = (float)raw[6]*1.364;
|
||
|
|
int temp = raw[7]-50;
|
||
|
|
int battery = raw[8]; /* This may be the battery. It's not clear. */
|
||
|
|
|
||
|
|
snprintf(info->name,sizeof(info->name),"%s","Citroen TPMS");
|
||
|
|
snprintf(info->raw,sizeof(info->raw),
|
||
|
|
"%02X%02X%02X%02X%02X%02X%02X%02X%02X%02X",
|
||
|
|
raw[0],raw[1],raw[2],raw[3],raw[4],raw[5],
|
||
|
|
raw[6],raw[7],raw[8],raw[9]);
|
||
|
|
snprintf(info->info1,sizeof(info->info1),"Tire ID %02X%02X%02X%02X",
|
||
|
|
raw[1],raw[2],raw[3],raw[4]);
|
||
|
|
snprintf(info->info2,sizeof(info->info2),"Pressure %.2f kpa", (double)kpa);
|
||
|
|
snprintf(info->info3,sizeof(info->info3),"Temperature %d C", temp);
|
||
|
|
snprintf(info->info4,sizeof(info->info4),"Repeat %d, Bat %d", repeat, battery);
|
||
|
|
return true;
|
||
|
|
}
|
||
|
|
|
||
|
|
ProtoViewDecoder CitroenTPMSDecoder = {
|
||
|
|
"Citroen TPMS", decode
|
||
|
|
};
|