/* PT/SC remotes. Usually 443.92 Mhz OOK. * * This line code is used in many remotes such as Princeton chips * named PT2262, Silian Microelectronics SC5262 and others. * Basically every 4 pulsee represent a bit, where 1000 means 0, and * 1110 means 1. Usually we can read 24 bits of data. * In this specific implementation we check for a prelude that is * 1 bit high, 31 bits low, but the check is relaxed. */ #include "../app.h" static bool decode(uint8_t* bits, uint32_t numbytes, uint32_t numbits, ProtoViewMsgInfo* info) { if(numbits < 30) return false; const char* sync_patterns[3] = { "10000000000000000000000000000001", /* 30 zero bits. */ "100000000000000000000000000000001", /* 31 zero bits. */ "1000000000000000000000000000000001", /* 32 zero bits. */ }; uint32_t off; int j; for(j = 0; j < 3; j++) { off = bitmap_seek_bits(bits, numbytes, 0, numbits, sync_patterns[j]); if(off != BITMAP_SEEK_NOT_FOUND) break; } if(off == BITMAP_SEEK_NOT_FOUND) return false; if(DEBUG_MSG) FURI_LOG_E(TAG, "B4B1 preamble at: %lu", off); info->start_off = off; // Seek data setction. Why -1? Last bit is data. off += strlen(sync_patterns[j]) - 1; uint8_t d[3]; /* 24 bits of data. */ uint32_t decoded = convert_from_line_code(d, sizeof(d), bits, numbytes, off, "1000", "1110"); if(DEBUG_MSG) FURI_LOG_E(TAG, "B4B1 decoded: %lu", decoded); if(decoded < 24) return false; off += 24 * 4; // seek to end symbol offset to calculate the length. off++; // In this protocol there is a final pulse as terminator. info->pulses_count = off - info->start_off; snprintf(info->name, PROTOVIEW_MSG_STR_LEN, "PT/SC remote"); snprintf(info->raw, PROTOVIEW_MSG_STR_LEN, "%02X%02X%02X", d[0], d[1], d[2]); return true; } ProtoViewDecoder B4B1Decoder = {"B4B1", decode};