diff options
Diffstat (limited to 'tools/ootx_decode/ootx_decoder.c')
-rw-r--r-- | tools/ootx_decode/ootx_decoder.c | 60 |
1 files changed, 9 insertions, 51 deletions
diff --git a/tools/ootx_decode/ootx_decoder.c b/tools/ootx_decode/ootx_decoder.c index 510fadb..5c64898 100644 --- a/tools/ootx_decode/ootx_decoder.c +++ b/tools/ootx_decode/ootx_decoder.c @@ -39,55 +39,16 @@ void ootx_free_decoder_context(ootx_decoder_context *ctx) { ctx->payload_size = NULL; } -/* - how to decode pulses - ticks>2000 && delta>100000== master lighthouse - ticks>2000 && delta>10000 == slave lighthouse -*/ - -int8_t ootx_decode_lighthouse_number(uint8_t last_num, uint32_t ticks, int32_t delta) { - if (delta<18000) return -1; //sweep -// if (ticks<2000) return -1; //sweep -// printf ("%d\n", delta); - - - if (ticks>2000 && delta>100000) return 0; //master - if (delta>100000) return -1; //some kind of sweep related to the master - - /* slaves are tricky. The first few sensor readings can be confused because their tick count could be too low because of the previous master pulse? - so we have to ignore ticks completly - */ - if (delta>18000) return 1; //a slave, should be at least 20000 but there are some data issues - return -1; -} - uint8_t ootx_decode_bit(uint32_t length) { uint8_t t = (length - 2750) / 500; //why 2750? -// return ((t & 0x02)>0)?0xFF:0x00; +// return ((t & 0x02)>0)?0xFF:0x00; //easier if we need to bitshift right return ((t & 0x02)>>1); } -void ootx_accumulate_bit(ootx_decoder_context *ctx, uint8_t bit) { - ctx->bit_count[bit&0x01]++; -} - -uint8_t ootx_pump_greatest_bit(ootx_decoder_context *ctx) { - //pump the bit - uint8_t bit = 0x00; - if (ctx->bit_count[0] < ctx->bit_count[1]) bit = 0xFF; - -// printf("pump %d\n", bit); - ootx_pump_bit( ctx, bit ); - - ctx->bit_count[0] = 0; - ctx->bit_count[1] = 0; - - return bit; -} - uint8_t ootx_detect_preamble(ootx_decoder_context *ctx, uint8_t dbit) { ctx->preamble <<= 1; - ctx->preamble |= (0x01 & dbit); +// ctx->preamble |= (0x01 & dbit); + ctx->preamble |= dbit; if ((ctx->preamble & 0x0003ffff) == 0x00000001) return 1; return 0; } @@ -115,11 +76,11 @@ void ootx_inc_buffer_offset(ootx_decoder_context *ctx) { void ootx_write_to_buffer(ootx_decoder_context *ctx, uint8_t dbit) { uint8_t *current_byte = ctx->buffer + ctx->buf_offset; -// printf("%d\n", dbit); -// *current_byte >>= 1; -// *current_byte |= (0x80 & dbit); + *current_byte <<= 1; - *current_byte |= (0x01 & dbit); +// *current_byte |= (0x01 & dbit); + *current_byte |= dbit; + ++(ctx->bits_written); if (ctx->bits_written>7) { ctx->bits_written=0; @@ -128,19 +89,16 @@ void ootx_write_to_buffer(ootx_decoder_context *ctx, uint8_t dbit) { } } -void ootx_process_bit(ootx_decoder_context *ctx, uint32_t length) { +uint8_t ootx_process_bit(ootx_decoder_context *ctx, uint32_t length) { uint8_t dbit = ootx_decode_bit(length); - ootx_pump_bit( ctx, dbit ); + return dbit; } void ootx_pump_bit(ootx_decoder_context *ctx, uint8_t dbit) { // uint8_t dbit = ootx_decode_bit(length); ++(ctx->bits_processed); -// printf("z %d %d\n", bits_processed,dbit); -// printf("d %d\n", bits_processed,dbit); - if ( ootx_detect_preamble(ctx, dbit) ) { /* data stream can start over at any time so we must always look for preamble bits */ |