From 7381e8f2f285aad4ce3919fa1964638cc08c3899 Mon Sep 17 00:00:00 2001 From: d18c7db Date: Thu, 6 Aug 2009 12:53:06 +0000 Subject: [PATCH] Added tiread command to demod TI tags on the PM3 --- armsrc/appmain.c | 16 +--- armsrc/apps.h | 2 +- armsrc/lfops.c | 230 +++++++++++++++++++++++++++++++++++---------- include/usb_cmd.h | 2 - winsrc/command.cpp | 169 ++++++++++++++------------------- 5 files changed, 255 insertions(+), 164 deletions(-) diff --git a/armsrc/appmain.c b/armsrc/appmain.c index 7dba687f..74448fe5 100644 --- a/armsrc/appmain.c +++ b/armsrc/appmain.c @@ -597,10 +597,6 @@ void UsbPacketReceived(BYTE *packet, int len) LED_D_OFF(); // LED D indicates field ON or OFF break; - case CMD_ACQUIRE_RAW_BITS_TI_TYPE: - AcquireRawBitsTI(); - break; - case CMD_READ_TI_TYPE: ReadTItag(); break; @@ -609,8 +605,7 @@ void UsbPacketReceived(BYTE *packet, int len) WriteTItag(c->ext1,c->ext2,c->ext3); break; - case CMD_DOWNLOAD_RAW_ADC_SAMPLES_125K: - case CMD_DOWNLOAD_RAW_BITS_TI_TYPE: { + case CMD_DOWNLOAD_RAW_ADC_SAMPLES_125K: { UsbCommand n; if(c->cmd == CMD_DOWNLOAD_RAW_ADC_SAMPLES_125K) { n.cmd = CMD_DOWNLOADED_RAW_ADC_SAMPLES_125K; @@ -632,11 +627,6 @@ void UsbPacketReceived(BYTE *packet, int len) SimulateTagLowFrequency(c->ext1, 1); LED_A_OFF(); break; -#ifdef WITH_LCD - case CMD_LCD_RESET: - LCDReset(); - break; -#endif case CMD_READ_MEM: ReadMem(c->ext1); break; @@ -644,6 +634,9 @@ void UsbPacketReceived(BYTE *packet, int len) FpgaSendCommand(FPGA_CMD_SET_DIVISOR, c->ext1); break; #ifdef WITH_LCD + case CMD_LCD_RESET: + LCDReset(); + break; case CMD_LCD: LCDSend(c->ext1); break; @@ -660,7 +653,6 @@ void UsbPacketReceived(BYTE *packet, int len) } break; - default: DbpString("unknown command"); break; diff --git a/armsrc/apps.h b/armsrc/apps.h index af6006e7..878ec526 100644 --- a/armsrc/apps.h +++ b/armsrc/apps.h @@ -9,7 +9,7 @@ // The large multi-purpose buffer, typically used to hold A/D samples, // maybe processed in some way. -DWORD BigBuf[10000]; +DWORD BigBuf[12000]; /// appmain.h void ReadMem(int addr); diff --git a/armsrc/lfops.c b/armsrc/lfops.c index 6ac4e725..f9aee43e 100644 --- a/armsrc/lfops.c +++ b/armsrc/lfops.c @@ -115,15 +115,181 @@ void ModThenAcquireRawAdcSamples125k(int delay_off,int period_0,int period_1,BYT DoAcquisition125k(at134khz); } +/* blank r/w tag data stream +...0000000000000000 01111111 +1010101010101010101010101010101010101010101010101010101010101010 +0011010010100001 +01111111 +101010101010101[0]000... + +[5555fe852c5555555555555555fe0000] +*/ +void ReadTItag() +{ + // some hardcoded initial params + // when we read a TI tag we sample the zerocross line at 2Mhz + // TI tags modulate a 1 as 16 cycles of 123.2Khz + // TI tags modulate a 0 as 16 cycles of 134.2Khz + #define FSAMPLE 2000000 + #define FREQLO 123200 + #define FREQHI 134200 + + signed char *dest = (signed char *)BigBuf; + int n = sizeof(BigBuf); +// int *dest = GraphBuffer; +// int n = GraphTraceLen; + + // 128 bit shift register [shift3:shift2:shift1:shift0] + DWORD shift3 = 0, shift2 = 0, shift1 = 0, shift0 = 0; + + int i, cycles=0, samples=0; + // how many sample points fit in 16 cycles of each frequency + DWORD sampleslo = (FSAMPLE<<4)/FREQLO, sampleshi = (FSAMPLE<<4)/FREQHI; + // when to tell if we're close enough to one freq or another + DWORD threshold = (sampleslo - sampleshi + 1)>>1; + + // TI tags charge at 134.2Khz + FpgaSendCommand(FPGA_CMD_SET_DIVISOR, 88); //134.8Khz + + // Place FPGA in passthrough mode, in this mode the CROSS_LO line + // connects to SSP_DIN and the SSP_DOUT logic level controls + // whether we're modulating the antenna (high) + // or listening to the antenna (low) + FpgaWriteConfWord(FPGA_MAJOR_MODE_LF_PASSTHRU); + + // get TI tag data into the buffer + AcquireTiType(); + + FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF); + + for (i=0; i0) ) { + cycles++; + // after 16 cycles, measure the frequency + if (cycles>15) { + cycles=0; + samples=i-samples; // number of samples in these 16 cycles + + // TI bits are coming to us lsb first so shift them + // right through our 128 bit right shift register + shift0 = (shift0>>1) | (shift1 << 31); + shift1 = (shift1>>1) | (shift2 << 31); + shift2 = (shift2>>1) | (shift3 << 31); + shift3 >>= 1; + + // check if the cycles fall close to the number + // expected for either the low or high frequency + if ( (samples>(sampleslo-threshold)) && (samples<(sampleslo+threshold)) ) { + // low frequency represents a 1 + shift3 |= (1<<31); + } else if ( (samples>(sampleshi-threshold)) && (samples<(sampleshi+threshold)) ) { + // high frequency represents a 0 + } else { + // probably detected a gay waveform or noise + // use this as gaydar or discard shift register and start again + shift3 = shift2 = shift1 = shift0 = 0; + } + samples = i; + + // for each bit we receive, test if we've detected a valid tag + + // if we see 17 zeroes followed by 6 ones, we might have a tag + // remember the bits are backwards + if ( ((shift0 & 0x7fffff) == 0x7e0000) ) { + // if start and end bytes match, we have a tag so break out of the loop + if ( ((shift0>>16)&0xff) == ((shift3>>8)&0xff) ) { + cycles = 0xF0B; //use this as a flag (ugly but whatever) + break; + } + } + } + } + } + + // if flag is set we have a tag + if (cycles!=0xF0B) { + DbpString("Info: No valid tag detected."); + } else { + // put 64 bit data into shift1 and shift0 + shift0 = (shift0>>24) | (shift1 << 8); + shift1 = (shift1>>24) | (shift2 << 8); + + // align 16 bit crc into lower half of shift2 + shift2 = ((shift2>>24) | (shift3 << 8)) & 0x0ffff; + + // if r/w tag, check ident match + if ( shift3&(1<<15) ) { + DbpString("Info: TI tag is rewriteable"); + // only 15 bits compare, last bit of ident is not valid + if ( ((shift3>>16)^shift0)&0x7fff ) { + DbpString("Error: Ident mismatch!"); + } else { + DbpString("Info: TI tag ident is valid"); + } + } else { + DbpString("Info: TI tag is readonly"); + } + + // WARNING the order of the bytes in which we calc crc below needs checking + // i'm 99% sure the crc algorithm is correct, but it may need to eat the + // bytes in reverse or something + // calculate CRC + DWORD crc=0; + + crc = update_crc16(crc, (shift0)&0xff); + crc = update_crc16(crc, (shift0>>8)&0xff); + crc = update_crc16(crc, (shift0>>16)&0xff); + crc = update_crc16(crc, (shift0>>24)&0xff); + crc = update_crc16(crc, (shift1)&0xff); + crc = update_crc16(crc, (shift1>>8)&0xff); + crc = update_crc16(crc, (shift1>>16)&0xff); + crc = update_crc16(crc, (shift1>>24)&0xff); + + DbpString("Info: Tag data_hi, data_lo, crc = "); + DbpIntegers(shift1, shift0, shift2&0xffff); + if (crc != (shift2&0xffff)) { + DbpString("Error: CRC mismatch, expected"); + DbpIntegers(0, 0, crc); + } else { + DbpString("Info: CRC is good"); + } + } +} + +void WriteTIbyte(BYTE b) +{ + int i = 0; + + // modulate 8 bits out to the antenna + for (i=0; i<8; i++) + { + if (b&(1<= n) return; + i++; if(i >= TIBUFLEN) break; } WDT_HIT(); } @@ -171,54 +337,22 @@ void AcquireTiType(void) // return stolen pin to SSP PIO_DISABLE = (1<=0; i--) { +// DbpIntegers(0, 0, BigBuf[i]); + for (j=0; j<32; j++) { + if(BigBuf[i] & (1 << j)) { + dest[--n] = 1; + } else { + dest[--n] = -1; + } } } } -void AcquireRawBitsTI(void) -{ - // TI tags charge at 134.2Khz - FpgaSendCommand(FPGA_CMD_SET_DIVISOR, 88); //134.8Khz - - // Place FPGA in passthrough mode, in this mode the CROSS_LO line - // connects to SSP_DIN and the SSP_DOUT logic level controls - // whether we're modulating the antenna (high) - // or listening to the antenna (low) - FpgaWriteConfWord(FPGA_MAJOR_MODE_LF_PASSTHRU); - - // get TI tag data into the buffer - AcquireTiType(); - - FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF); -} - // arguments: 64bit data split into 32bit idhi:idlo and optional 16bit crc // if crc provided, it will be written with the data verbatim (even if bogus) // if not provided a valid crc will be computed from the data and written. @@ -292,7 +426,7 @@ void WriteTItag(DWORD idhi, DWORD idlo, WORD crc) AcquireTiType(); FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF); - DbpString("Now use tibits and tidemod"); + DbpString("Now use tiread to check"); } void SimulateTagLowFrequency(int period, int ledcontrol) diff --git a/include/usb_cmd.h b/include/usb_cmd.h index 8245bae2..6818bb5e 100644 --- a/include/usb_cmd.h +++ b/include/usb_cmd.h @@ -37,8 +37,6 @@ typedef struct { #define CMD_READ_MEM 0x0106 // For low-frequency tags -#define CMD_ACQUIRE_RAW_BITS_TI_TYPE 0x0200 -#define CMD_DOWNLOAD_RAW_BITS_TI_TYPE 0x0201 #define CMD_READ_TI_TYPE 0x0202 #define CMD_WRITE_TI_TYPE 0x0203 #define CMD_DOWNLOADED_RAW_BITS_TI_TYPE 0x0204 diff --git a/winsrc/command.cpp b/winsrc/command.cpp index 454fbab2..08feb3dd 100644 --- a/winsrc/command.cpp +++ b/winsrc/command.cpp @@ -1397,45 +1397,6 @@ static void CmdHi15demod(char *str) PrintToScrollback("CRC=%04x", Iso15693Crc(outBuf, k-2)); } -static void CmdTIReadRaw(char *str) -{ - UsbCommand c; - c.cmd = CMD_ACQUIRE_RAW_BITS_TI_TYPE; - SendCommand(&c, FALSE); -} - -static void CmdTIBits(char *str) -{ - int cnt = 0; - int i; -// for(i = 0; i < 1536; i += 12) { - for(i = 0; i < 4000; i += 12) { - UsbCommand c; - c.cmd = CMD_DOWNLOAD_RAW_BITS_TI_TYPE; - c.ext1 = i; - SendCommand(&c, FALSE); - ReceiveCommand(&c); - if(c.cmd != CMD_DOWNLOADED_RAW_BITS_TI_TYPE) { - PrintToScrollback("bad resp"); - return; - } - int j; - for(j = 0; j < 12; j++) { - int k; - for(k = 31; k >= 0; k--) { - if(c.d.asDwords[j] & (1 << k)) { - GraphBuffer[cnt++] = 1; - } else { - GraphBuffer[cnt++] = -1; - } - } - } - } -// GraphTraceLen = 1536*32; - GraphTraceLen = 4000*32; - RepaintGraphWindow(); -} - static void CmdFSKdemod(char *cmdline) { static const int LowTone[] = { @@ -1454,13 +1415,13 @@ static void CmdFSKdemod(char *cmdline) 1, 1, 1, 1, -1, -1, -1, -1, -1, }; - int convLen = max(arraylen(HighTone), arraylen(LowTone)); + int lowLen = sizeof(LowTone)/sizeof(int); + int highLen = sizeof(HighTone)/sizeof(int); + int convLen = (highLen>lowLen)?highLen:lowLen; DWORD hi = 0, lo = 0; int i, j; int minMark=0, maxMark=0; - int lowLen = arraylen(LowTone); - int highLen = arraylen(HighTone); for(i = 0; i < GraphTraceLen - convLen; i++) { int lowSum = 0, highSum = 0; @@ -1499,10 +1460,10 @@ static void CmdFSKdemod(char *cmdline) int max = 0, maxPos = 0; for(i = 0; i < 6000; i++) { int dec = 0; - for(j = 0; j < 3*arraylen(LowTone); j++) { + for(j = 0; j < 3*lowLen; j++) { dec -= GraphBuffer[i+j]; } - for(; j < 3*(arraylen(LowTone) + arraylen(HighTone) ); j++) { + for(; j < 3*(lowLen + highLen ); j++) { dec += GraphBuffer[i+j]; } if(dec > max) { @@ -1522,7 +1483,7 @@ static void CmdFSKdemod(char *cmdline) GraphBuffer[maxPos+1] = minMark; PrintToScrollback("actual data bits start at sample %d", maxPos); - PrintToScrollback("length %d/%d", arraylen(HighTone), arraylen(LowTone)); + PrintToScrollback("length %d/%d", highLen, lowLen); BYTE bits[46]; bits[sizeof(bits)-1] = '\0'; @@ -1530,10 +1491,10 @@ static void CmdFSKdemod(char *cmdline) // find bit pairs and manchester decode them for(i = 0; i < arraylen(bits)-1; i++) { int dec = 0; - for(j = 0; j < arraylen(LowTone); j++) { + for(j = 0; j < lowLen; j++) { dec -= GraphBuffer[maxPos+j]; } - for(; j < arraylen(LowTone) + arraylen(HighTone); j++) { + for(; j < lowLen + highLen; j++) { dec += GraphBuffer[maxPos+j]; } maxPos += j; @@ -1574,7 +1535,7 @@ static void CmdTIWrite(char *str) res = sscanf(str, "0x%x 0x%x 0x%x ", &c.ext1, &c.ext2, &c.ext3); if (res == 2) c.ext3=0; if (res<2) - PrintToScrollback("Please specify 2 or three hex strings, eg 0x1234 0x5678"); + PrintToScrollback("Please specify the data as two hex strings, optionally the CRC as a third"); else SendCommand(&c, FALSE); } @@ -1595,52 +1556,57 @@ h = 2*pi*ones(1, floor(f_s*T_h))*(f_h/f_s); l = sign(sin(cumsum(l))); h = sign(sin(cumsum(h))); */ + +// 2M*16/134.2k = 238 static const int LowTone[] = { - 1, 1, 1, 1, 1, 1, 1, 1, -1, -1, -1, -1, -1, -1, -1, -1, - 1, 1, 1, 1, 1, 1, 1, 1, -1, -1, -1, -1, -1, -1, -1, -1, - 1, 1, 1, 1, 1, 1, 1, 1, -1, -1, -1, -1, -1, -1, -1, -1, - 1, 1, 1, 1, 1, 1, 1, 1, -1, -1, -1, -1, -1, -1, -1, -1, - 1, 1, 1, 1, 1, 1, 1, 1, 1, -1, -1, -1, -1, -1, -1, -1, -1, - 1, 1, 1, 1, 1, 1, 1, 1, -1, -1, -1, -1, -1, -1, -1, -1, - 1, 1, 1, 1, 1, 1, 1, 1, -1, -1, -1, -1, -1, -1, -1, -1, - 1, 1, 1, 1, 1, 1, 1, 1, -1, -1, -1, -1, -1, -1, -1, -1, - 1, 1, 1, 1, 1, 1, 1, 1, -1, -1, -1, -1, -1, -1, -1, -1, -1, - 1, 1, 1, 1, 1, 1, 1, 1, -1, -1, -1, -1, -1, -1, -1, -1, - 1, 1, 1, 1, 1, 1, 1, 1, -1, -1, -1, -1, -1, -1, -1, -1, - 1, 1, 1, 1, 1, 1, 1, 1, -1, -1, -1, -1, -1, -1, -1, -1, - 1, 1, 1, 1, 1, 1, 1, 1, -1, -1, -1, -1, -1, -1, -1, -1, -1, - 1, 1, 1, 1, 1, 1, 1, 1, -1, -1, -1, -1, -1, -1, -1, -1, - 1, 1, 1, 1, 1, 1, 1, 1, -1, -1, -1, + 1, 1, 1, 1, 1, 1, 1, 1, 1, -1, -1, -1, -1, -1, -1, -1, -1, + 1, 1, 1, 1, 1, 1, 1, 1, -1, -1, -1, -1, -1, -1, -1, -1, + 1, 1, 1, 1, 1, 1, 1, 1, -1, -1, -1, -1, -1, -1, -1, -1, + 1, 1, 1, 1, 1, 1, 1, 1, -1, -1, -1, -1, -1, -1, -1, -1, + 1, 1, 1, 1, 1, 1, 1, 1, 1, -1, -1, -1, -1, -1, -1, -1, -1, + 1, 1, 1, 1, 1, 1, 1, 1, -1, -1, -1, -1, -1, -1, -1, -1, + 1, 1, 1, 1, 1, 1, 1, 1, -1, -1, -1, -1, -1, -1, -1, -1, + 1, 1, 1, 1, 1, 1, 1, 1, -1, -1, -1, -1, -1, -1, -1, -1, + 1, 1, 1, 1, 1, 1, 1, 1, 1, -1, -1, -1, -1, -1, -1, -1, -1, + 1, 1, 1, 1, 1, 1, 1, 1, -1, -1, -1, -1, -1, -1, -1, -1, + 1, 1, 1, 1, 1, 1, 1, 1, -1, -1, -1, -1, -1, -1, -1, -1, + 1, 1, 1, 1, 1, 1, 1, 1, -1, -1, -1, -1, -1, -1, -1, -1, + 1, 1, 1, 1, 1, 1, 1, 1, 1, -1, -1, -1, -1, -1, -1, -1, -1, + 1, 1, 1, 1, 1, 1, 1, 1, -1, -1, -1, -1, -1, -1, -1, -1, + 1, 1, 1, 1, 1, 1, 1, 1, -1, -1 }; +// 2M*16/123.2k = 260 static const int HighTone[] = { - 1, 1, 1, 1, 1, 1, 1, -1, -1, -1, -1, -1, -1, -1, - 1, 1, 1, 1, 1, 1, 1, 1, -1, -1, -1, -1, -1, -1, -1, - 1, 1, 1, 1, 1, 1, 1, 1, -1, -1, -1, -1, -1, -1, -1, - 1, 1, 1, 1, 1, 1, 1, 1, -1, -1, -1, -1, -1, -1, -1, - 1, 1, 1, 1, 1, 1, 1, 1, -1, -1, -1, -1, -1, -1, -1, - 1, 1, 1, 1, 1, 1, 1, -1, -1, -1, -1, -1, -1, -1, -1, - 1, 1, 1, 1, 1, 1, 1, -1, -1, -1, -1, -1, -1, -1, -1, - 1, 1, 1, 1, 1, 1, 1, -1, -1, -1, -1, -1, -1, -1, -1, - 1, 1, 1, 1, 1, 1, 1, -1, -1, -1, -1, -1, -1, -1, -1, - 1, 1, 1, 1, 1, 1, 1, -1, -1, -1, -1, -1, -1, -1, -1, - 1, 1, 1, 1, 1, 1, 1, -1, -1, -1, -1, -1, -1, -1, - 1, 1, 1, 1, 1, 1, 1, 1, -1, -1, -1, -1, -1, -1, -1, - 1, 1, 1, 1, 1, 1, 1, 1, -1, -1, -1, -1, -1, -1, -1, - 1, 1, 1, 1, 1, 1, 1, 1, -1, -1, -1, -1, -1, -1, -1, - 1, 1, 1, 1, 1, 1, 1, 1, -1, -1, -1, -1, -1, -1, -1, - 1, 1, 1, 1, 1, 1, 1, -1, -1, -1, -1, -1, -1, -1, -1, - 1, 1, 1, 1, 1, 1, 1, -1, -1, -1, -1, -1, -1, -1, -1, - 1, 1, 1, 1, 1, 1, 1, + 1, 1, 1, 1, 1, 1, 1, 1, -1, -1, -1, -1, -1, -1, -1, + 1, 1, 1, 1, 1, 1, 1, 1, -1, -1, -1, -1, -1, -1, -1, + 1, 1, 1, 1, 1, 1, 1, -1, -1, -1, -1, -1, -1, -1, -1, + 1, 1, 1, 1, 1, 1, 1, -1, -1, -1, -1, -1, -1, -1, -1, + 1, 1, 1, 1, 1, 1, 1, -1, -1, -1, -1, -1, -1, -1, -1, + 1, 1, 1, 1, 1, 1, 1, -1, -1, -1, -1, -1, -1, -1, + 1, 1, 1, 1, 1, 1, 1, 1, -1, -1, -1, -1, -1, -1, -1, + 1, 1, 1, 1, 1, 1, 1, 1, -1, -1, -1, -1, -1, -1, -1, + 1, 1, 1, 1, 1, 1, 1, -1, -1, -1, -1, -1, -1, -1, -1, + 1, 1, 1, 1, 1, 1, 1, -1, -1, -1, -1, -1, -1, -1, -1, + 1, 1, 1, 1, 1, 1, 1, -1, -1, -1, -1, -1, -1, -1, + 1, 1, 1, 1, 1, 1, 1, 1, -1, -1, -1, -1, -1, -1, -1, + 1, 1, 1, 1, 1, 1, 1, 1, -1, -1, -1, -1, -1, -1, -1, + 1, 1, 1, 1, 1, 1, 1, 1, -1, -1, -1, -1, -1, -1, -1, + 1, 1, 1, 1, 1, 1, 1, -1, -1, -1, -1, -1, -1, -1, -1, + 1, 1, 1, 1, 1, 1, 1, -1, -1, -1, -1, -1, -1, -1, -1, + 1, 1, 1, 1, 1, 1, 1, -1, -1, -1, -1, -1, -1, -1, + 1, 1, 1, 1, 1, 1, 1, 1 }; - - int convLen = max(arraylen(HighTone), arraylen(LowTone)); + int lowLen = sizeof(LowTone)/sizeof(int); + int highLen = sizeof(HighTone)/sizeof(int); + int convLen = (highLen>lowLen)?highLen:lowLen; WORD crc; - int i, TagType; + int i, j, TagType; + int lowSum = 0, highSum = 0;; + int lowTot = 0, highTot = 0; + for(i = 0; i < GraphTraceLen - convLen; i++) { - int j; - int lowSum = 0, highSum = 0;; - int lowLen = arraylen(LowTone); - int highLen = arraylen(HighTone); + lowSum = 0; + highSum = 0;; for(j = 0; j < lowLen; j++) { lowSum += LowTone[j]*GraphBuffer[i+j]; @@ -1650,12 +1616,15 @@ h = sign(sin(cumsum(h))); } lowSum = abs((100*lowSum) / lowLen); highSum = abs((100*highSum) / highLen); + lowSum = (lowSum<0)?-lowSum:lowSum; + highSum = (highSum<0)?-highSum:highSum; + GraphBuffer[i] = (highSum << 16) | lowSum; } for(i = 0; i < GraphTraceLen - convLen - 16; i++) { - int j; - int lowTot = 0, highTot = 0; + lowTot = 0; + highTot = 0; // 16 and 15 are f_s divided by f_l and f_h, rounded for(j = 0; j < 16; j++) { lowTot += (GraphBuffer[i+j] & 0xffff); @@ -1688,11 +1657,11 @@ h = sign(sin(cumsum(h))); int j; int dec = 0; // searching 17 consecutive lows - for(j = 0; j < 17*arraylen(LowTone); j++) { + for(j = 0; j < 17*lowLen; j++) { dec -= GraphBuffer[i+j]; } // searching 7 consecutive highs - for(; j < 17*arraylen(LowTone) + 6*arraylen(HighTone); j++) { + for(; j < 17*lowLen + 6*highLen; j++) { dec += GraphBuffer[i+j]; } if(dec > max) { @@ -1707,8 +1676,8 @@ h = sign(sin(cumsum(h))); GraphBuffer[maxPos+1] = -800; // advance pointer to start of actual data stream (after 16 pre and 8 start bits) - maxPos += 17*arraylen(LowTone); - maxPos += 6*arraylen(HighTone); + maxPos += 17*lowLen; + maxPos += 6*highLen; // place a marker in the buffer to visually aid location // of the end of sync @@ -1717,7 +1686,7 @@ h = sign(sin(cumsum(h))); PrintToScrollback("actual data bits start at sample %d", maxPos); - PrintToScrollback("length %d/%d", arraylen(HighTone), arraylen(LowTone)); + PrintToScrollback("length %d/%d", highLen, lowLen); BYTE bits[1+64+16+8+16]; bits[sizeof(bits)-1] = '\0'; @@ -1728,21 +1697,21 @@ h = sign(sin(cumsum(h))); int high = 0; int low = 0; int j; - for(j = 0; j < arraylen(LowTone); j++) { + for(j = 0; j < lowLen; j++) { low -= GraphBuffer[maxPos+j]; } - for(j = 0; j < arraylen(HighTone); j++) { + for(j = 0; j < highLen; j++) { high += GraphBuffer[maxPos+j]; } if(high > low) { bits[i] = '1'; - maxPos += arraylen(HighTone); + maxPos += highLen; // bitstream arrives lsb first so shift right shift3 |= (1<<31); } else { bits[i] = '.'; - maxPos += arraylen(LowTone); + maxPos += lowLen; } // 128 bit right shift register @@ -2870,9 +2839,7 @@ static struct { {"scale", CmdScale, 1, " -- Set cursor display scale"}, {"setlfdivisor", CmdSetDivisor, 0, "<19 - 255> -- Drive LF antenna at 12Mhz/(divisor+1)"}, {"sri512read", CmdSri512read, 0, " -- Read contents of a SRI512 tag"}, - {"tibits", CmdTIBits, 0, "Get raw bits for TI-type LF tag"}, {"tidemod", CmdTIDemod, 1, "Demodulate raw bits for TI-type LF tag"}, - {"tireadraw", CmdTIReadRaw, 0, "Read a TI-type 134 kHz tag in raw mode"}, {"tiread", CmdTIRead, 0, "Read and decode a TI 134 kHz tag"}, {"tiwrite", CmdTIWrite, 0, "Write new data to a r/w TI 134 kHz tag"}, {"threshold", CmdThreshold, 1, "Maximize/minimize every value in the graph window depending on threshold"}, -- 2.39.2