fixing iso14443b (issue #103):

- increased DMA_BUFFER_SIZE to avoid occasional circular buffer overflows.
- minor code cleanups

diff --git a/armsrc/iso14443b.c b/armsrc/iso14443b.c
index 1ae1692b932270671298863365a1a033368a2171..416c31f93142e9f819393a327ae132497909d9c0 100644 (file)
--- a/armsrc/iso14443b.c
+++ b/armsrc/iso14443b.c
@@ -17,6 +17,7 @@
 #include "iso14443crc.h"
 
 #define RECEIVE_SAMPLES_TIMEOUT 2000
 #include "iso14443crc.h"
 
 #define RECEIVE_SAMPLES_TIMEOUT 2000

+#define ISO14443B_DMA_BUFFER_SIZE 256

 
 //=============================================================================
 // An ISO 14443 Type B tag. We listen for commands from the reader, using
 
 //=============================================================================
 // An ISO 14443 Type B tag. We listen for commands from the reader, using


@@ -717,16 +718,16 @@ static void GetSamplesFor14443bDemod(int n, bool quiet)
        uint8_t *receivedResponse = BigBuf_malloc(MAX_FRAME_SIZE);
        
        // The DMA buffer, used to stream samples from the FPGA
        uint8_t *receivedResponse = BigBuf_malloc(MAX_FRAME_SIZE);
        
        // The DMA buffer, used to stream samples from the FPGA

-       int8_t *dmaBuf = (int8_t*) BigBuf_malloc(DMA_BUFFER_SIZE);
+       int8_t *dmaBuf = (int8_t*) BigBuf_malloc(ISO14443B_DMA_BUFFER_SIZE);

 
        // Set up the demodulator for tag -> reader responses.
        DemodInit(receivedResponse);
 
        // Setup and start DMA.
 
        // Set up the demodulator for tag -> reader responses.
        DemodInit(receivedResponse);
 
        // Setup and start DMA.

-       FpgaSetupSscDma((uint8_t*) dmaBuf, DMA_BUFFER_SIZE);
+       FpgaSetupSscDma((uint8_t*) dmaBuf, ISO14443B_DMA_BUFFER_SIZE);

 
        int8_t *upTo = dmaBuf;
 
        int8_t *upTo = dmaBuf;

-       lastRxCounter = DMA_BUFFER_SIZE;
+       lastRxCounter = ISO14443B_DMA_BUFFER_SIZE;

 
        // Signal field is ON with the appropriate LED:
        LED_D_ON();
 
        // Signal field is ON with the appropriate LED:
        LED_D_ON();


@@ -737,18 +738,18 @@ static void GetSamplesFor14443bDemod(int n, bool quiet)
                int behindBy = lastRxCounter - AT91C_BASE_PDC_SSC->PDC_RCR;
                if(behindBy > max) max = behindBy;
 
                int behindBy = lastRxCounter - AT91C_BASE_PDC_SSC->PDC_RCR;
                if(behindBy > max) max = behindBy;
 

-               while(((lastRxCounter-AT91C_BASE_PDC_SSC->PDC_RCR) & (DMA_BUFFER_SIZE-1)) > 2) {
+               while(((lastRxCounter-AT91C_BASE_PDC_SSC->PDC_RCR) & (ISO14443B_DMA_BUFFER_SIZE-1)) > 2) {

                        ci = upTo[0];
                        cq = upTo[1];
                        upTo += 2;
                        ci = upTo[0];
                        cq = upTo[1];
                        upTo += 2;

-                       if(upTo >= dmaBuf + DMA_BUFFER_SIZE) {
+                       if(upTo >= dmaBuf + ISO14443B_DMA_BUFFER_SIZE) {

                                upTo = dmaBuf;
                                AT91C_BASE_PDC_SSC->PDC_RNPR = (uint32_t) upTo;
                                upTo = dmaBuf;
                                AT91C_BASE_PDC_SSC->PDC_RNPR = (uint32_t) upTo;

-                               AT91C_BASE_PDC_SSC->PDC_RNCR = DMA_BUFFER_SIZE;
+                               AT91C_BASE_PDC_SSC->PDC_RNCR = ISO14443B_DMA_BUFFER_SIZE;

                        }
                        lastRxCounter -= 2;
                        if(lastRxCounter <= 0) {
                        }
                        lastRxCounter -= 2;
                        if(lastRxCounter <= 0) {

-                               lastRxCounter += DMA_BUFFER_SIZE;
+                               lastRxCounter += ISO14443B_DMA_BUFFER_SIZE;

                        }
 
                        samples += 2;
                        }
 
                        samples += 2;


@@ -770,7 +771,6 @@ static void GetSamplesFor14443bDemod(int n, bool quiet)
        //Tracing
        if (tracing && Demod.len > 0) {
                uint8_t parity[MAX_PARITY_SIZE];
        //Tracing
        if (tracing && Demod.len > 0) {
                uint8_t parity[MAX_PARITY_SIZE];

-               //GetParity(Demod.output, Demod.len, parity);

                LogTrace(Demod.output, Demod.len, 0, 0, parity, FALSE);
        }
 }
                LogTrace(Demod.output, Demod.len, 0, 0, parity, FALSE);
        }
 }


@@ -892,7 +892,6 @@ static void CodeAndTransmit14443bAsReader(const uint8_t *cmd, int len)
        TransmitFor14443b();
        if (tracing) {
                uint8_t parity[MAX_PARITY_SIZE];
        TransmitFor14443b();
        if (tracing) {
                uint8_t parity[MAX_PARITY_SIZE];

-               GetParity(cmd, len, parity);

                LogTrace(cmd,len, 0, 0, parity, TRUE);
        }
 }
                LogTrace(cmd,len, 0, 0, parity, TRUE);
        }
 }


@@ -927,35 +926,29 @@ void ReadSTMemoryIso14443b(uint32_t dwLast)
        // Now give it time to spin up.
        // Signal field is on with the appropriate LED
        LED_D_ON();
        // Now give it time to spin up.
        // Signal field is on with the appropriate LED
        LED_D_ON();

-       FpgaWriteConfWord(
-               FPGA_MAJOR_MODE_HF_READER_RX_XCORR | FPGA_HF_READER_RX_XCORR_848_KHZ);
+       FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_READER_RX_XCORR | FPGA_HF_READER_RX_XCORR_848_KHZ);

        SpinDelay(200);
 
        // First command: wake up the tag using the INITIATE command
        uint8_t cmd1[] = {0x06, 0x00, 0x97, 0x5b};
        SpinDelay(200);
 
        // First command: wake up the tag using the INITIATE command
        uint8_t cmd1[] = {0x06, 0x00, 0x97, 0x5b};

-

        CodeAndTransmit14443bAsReader(cmd1, sizeof(cmd1));
        CodeAndTransmit14443bAsReader(cmd1, sizeof(cmd1));

-//    LED_A_ON();

        GetSamplesFor14443bDemod(RECEIVE_SAMPLES_TIMEOUT, TRUE);
        GetSamplesFor14443bDemod(RECEIVE_SAMPLES_TIMEOUT, TRUE);

-//    LED_A_OFF();

 
        if (Demod.len == 0) {
 
        if (Demod.len == 0) {

-       DbpString("No response from tag");
-       return;
+               DbpString("No response from tag");
+               return;

        } else {
        } else {

-       Dbprintf("Randomly generated UID from tag (+ 2 byte CRC): %02x %02x %02x",
-               Demod.output[0], Demod.output[1], Demod.output[2]);
+               Dbprintf("Randomly generated Chip ID (+ 2 byte CRC): %02x %02x %02x",
+                               Demod.output[0], Demod.output[1], Demod.output[2]);

        }
        }

+

        // There is a response, SELECT the uid
        DbpString("Now SELECT tag:");
        cmd1[0] = 0x0E; // 0x0E is SELECT
        cmd1[1] = Demod.output[0];
        ComputeCrc14443(CRC_14443_B, cmd1, 2, &cmd1[2], &cmd1[3]);
        CodeAndTransmit14443bAsReader(cmd1, sizeof(cmd1));
        // There is a response, SELECT the uid
        DbpString("Now SELECT tag:");
        cmd1[0] = 0x0E; // 0x0E is SELECT
        cmd1[1] = Demod.output[0];
        ComputeCrc14443(CRC_14443_B, cmd1, 2, &cmd1[2], &cmd1[3]);
        CodeAndTransmit14443bAsReader(cmd1, sizeof(cmd1));

-
-//    LED_A_ON();

        GetSamplesFor14443bDemod(RECEIVE_SAMPLES_TIMEOUT, TRUE);
        GetSamplesFor14443bDemod(RECEIVE_SAMPLES_TIMEOUT, TRUE);

-//    LED_A_OFF();

        if (Demod.len != 3) {
                Dbprintf("Expected 3 bytes from tag, got %d", Demod.len);
                return;
        if (Demod.len != 3) {
                Dbprintf("Expected 3 bytes from tag, got %d", Demod.len);
                return;


@@ -971,15 +964,13 @@ void ReadSTMemoryIso14443b(uint32_t dwLast)
                Dbprintf("Bad response to SELECT from Tag, aborting: %02x %02x", cmd1[1], Demod.output[0]);
                return;
        }
                Dbprintf("Bad response to SELECT from Tag, aborting: %02x %02x", cmd1[1], Demod.output[0]);
                return;
        }

+

        // Tag is now selected,
        // First get the tag's UID:
        cmd1[0] = 0x0B;
        ComputeCrc14443(CRC_14443_B, cmd1, 1 , &cmd1[1], &cmd1[2]);
        CodeAndTransmit14443bAsReader(cmd1, 3); // Only first three bytes for this one
        // Tag is now selected,
        // First get the tag's UID:
        cmd1[0] = 0x0B;
        ComputeCrc14443(CRC_14443_B, cmd1, 1 , &cmd1[1], &cmd1[2]);
        CodeAndTransmit14443bAsReader(cmd1, 3); // Only first three bytes for this one

-
-//    LED_A_ON();

        GetSamplesFor14443bDemod(RECEIVE_SAMPLES_TIMEOUT, TRUE);
        GetSamplesFor14443bDemod(RECEIVE_SAMPLES_TIMEOUT, TRUE);

-//    LED_A_OFF();

        if (Demod.len != 10) {
                Dbprintf("Expected 10 bytes from tag, got %d", Demod.len);
                return;
        if (Demod.len != 10) {
                Dbprintf("Expected 10 bytes from tag, got %d", Demod.len);
                return;


@@ -988,12 +979,12 @@ void ReadSTMemoryIso14443b(uint32_t dwLast)
        ComputeCrc14443(CRC_14443_B, Demod.output, 8, &cmd1[2], &cmd1[3]);
        if(cmd1[2] != Demod.output[8] || cmd1[3] != Demod.output[9]) {
                Dbprintf("CRC Error reading block! Expected: %04x got: %04x",
        ComputeCrc14443(CRC_14443_B, Demod.output, 8, &cmd1[2], &cmd1[3]);
        if(cmd1[2] != Demod.output[8] || cmd1[3] != Demod.output[9]) {
                Dbprintf("CRC Error reading block! Expected: %04x got: %04x",

-                       (cmd1[2]<<8)+cmd1[3], (Demod.output[8]<<8)+Demod.output[9]);
+                               (cmd1[2]<<8)+cmd1[3], (Demod.output[8]<<8)+Demod.output[9]);

                // Do not return;, let's go on... (we should retry, maybe ?)
        }
        Dbprintf("Tag UID (64 bits): %08x %08x",
                // Do not return;, let's go on... (we should retry, maybe ?)
        }
        Dbprintf("Tag UID (64 bits): %08x %08x",

-               (Demod.output[7]<<24) + (Demod.output[6]<<16) + (Demod.output[5]<<8) + Demod.output[4],
-               (Demod.output[3]<<24) + (Demod.output[2]<<16) + (Demod.output[1]<<8) + Demod.output[0]);
+                       (Demod.output[7]<<24) + (Demod.output[6]<<16) + (Demod.output[5]<<8) + Demod.output[4],
+                       (Demod.output[3]<<24) + (Demod.output[2]<<16) + (Demod.output[1]<<8) + Demod.output[0]);

 
        // Now loop to read all 16 blocks, address from 0 to last block
        Dbprintf("Tag memory dump, block 0 to %d", dwLast);
 
        // Now loop to read all 16 blocks, address from 0 to last block
        Dbprintf("Tag memory dump, block 0 to %d", dwLast);


@@ -1008,10 +999,7 @@ void ReadSTMemoryIso14443b(uint32_t dwLast)
                cmd1[1] = i;
                ComputeCrc14443(CRC_14443_B, cmd1, 2, &cmd1[2], &cmd1[3]);
                CodeAndTransmit14443bAsReader(cmd1, sizeof(cmd1));
                cmd1[1] = i;
                ComputeCrc14443(CRC_14443_B, cmd1, 2, &cmd1[2], &cmd1[3]);
                CodeAndTransmit14443bAsReader(cmd1, sizeof(cmd1));

-
-//         LED_A_ON();

                GetSamplesFor14443bDemod(RECEIVE_SAMPLES_TIMEOUT, TRUE);
                GetSamplesFor14443bDemod(RECEIVE_SAMPLES_TIMEOUT, TRUE);

-//         LED_A_OFF();

                if (Demod.len != 6) { // Check if we got an answer from the tag
                        DbpString("Expected 6 bytes from tag, got less...");
                        return;
                if (Demod.len != 6) { // Check if we got an answer from the tag
                        DbpString("Expected 6 bytes from tag, got less...");
                        return;


@@ -1020,13 +1008,13 @@ void ReadSTMemoryIso14443b(uint32_t dwLast)
                ComputeCrc14443(CRC_14443_B, Demod.output, 4, &cmd1[2], &cmd1[3]);
                if(cmd1[2] != Demod.output[4] || cmd1[3] != Demod.output[5]) {
                        Dbprintf("CRC Error reading block! Expected: %04x got: %04x",
                ComputeCrc14443(CRC_14443_B, Demod.output, 4, &cmd1[2], &cmd1[3]);
                if(cmd1[2] != Demod.output[4] || cmd1[3] != Demod.output[5]) {
                        Dbprintf("CRC Error reading block! Expected: %04x got: %04x",

-                               (cmd1[2]<<8)+cmd1[3], (Demod.output[4]<<8)+Demod.output[5]);
+                                       (cmd1[2]<<8)+cmd1[3], (Demod.output[4]<<8)+Demod.output[5]);

                        // Do not return;, let's go on... (we should retry, maybe ?)
                }
                // Now print out the memory location:
                Dbprintf("Address=%02x, Contents=%08x, CRC=%04x", i,
                        // Do not return;, let's go on... (we should retry, maybe ?)
                }
                // Now print out the memory location:
                Dbprintf("Address=%02x, Contents=%08x, CRC=%04x", i,

-                       (Demod.output[3]<<24) + (Demod.output[2]<<16) + (Demod.output[1]<<8) + Demod.output[0],
-                       (Demod.output[4]<<8)+Demod.output[5]);
+                               (Demod.output[3]<<24) + (Demod.output[2]<<16) + (Demod.output[1]<<8) + Demod.output[0],
+                               (Demod.output[4]<<8)+Demod.output[5]);

                if (i == 0xff) {
                        break;
                }
                if (i == 0xff) {
                        break;
                }


@@ -1049,7 +1037,7 @@ void ReadSTMemoryIso14443b(uint32_t dwLast)
  * Memory usage for this function, (within BigBuf)
  * Last Received command (reader->tag) - MAX_FRAME_SIZE
  * Last Received command (tag->reader) - MAX_FRAME_SIZE
  * Memory usage for this function, (within BigBuf)
  * Last Received command (reader->tag) - MAX_FRAME_SIZE
  * Last Received command (tag->reader) - MAX_FRAME_SIZE

- * DMA Buffer - DMA_BUFFER_SIZE
+ * DMA Buffer - ISO14443B_DMA_BUFFER_SIZE

  * Demodulated samples received - all the rest
  */
 void RAMFUNC SnoopIso14443b(void)
  * Demodulated samples received - all the rest
  */
 void RAMFUNC SnoopIso14443b(void)


@@ -1066,7 +1054,7 @@ void RAMFUNC SnoopIso14443b(void)
        set_tracing(TRUE);
 
        // The DMA buffer, used to stream samples from the FPGA
        set_tracing(TRUE);
 
        // The DMA buffer, used to stream samples from the FPGA

-       int8_t *dmaBuf = (int8_t*) BigBuf_malloc(DMA_BUFFER_SIZE);
+       int8_t *dmaBuf = (int8_t*) BigBuf_malloc(ISO14443B_DMA_BUFFER_SIZE);

        int lastRxCounter;
        int8_t *upTo;
        int ci, cq;
        int lastRxCounter;
        int8_t *upTo;
        int ci, cq;


@@ -1084,7 +1072,7 @@ void RAMFUNC SnoopIso14443b(void)
        Dbprintf("  Trace: %i bytes", BigBuf_max_traceLen());
        Dbprintf("  Reader -> tag: %i bytes", MAX_FRAME_SIZE);
        Dbprintf("  tag -> Reader: %i bytes", MAX_FRAME_SIZE);
        Dbprintf("  Trace: %i bytes", BigBuf_max_traceLen());
        Dbprintf("  Reader -> tag: %i bytes", MAX_FRAME_SIZE);
        Dbprintf("  tag -> Reader: %i bytes", MAX_FRAME_SIZE);

-       Dbprintf("  DMA: %i bytes", DMA_BUFFER_SIZE);
+       Dbprintf("  DMA: %i bytes", ISO14443B_DMA_BUFFER_SIZE);

 
        // Signal field is off, no reader signal, no tag signal
        LEDsoff();
 
        // Signal field is off, no reader signal, no tag signal
        LEDsoff();


@@ -1096,8 +1084,8 @@ void RAMFUNC SnoopIso14443b(void)
        // Setup for the DMA.
        FpgaSetupSsc();
        upTo = dmaBuf;
        // Setup for the DMA.
        FpgaSetupSsc();
        upTo = dmaBuf;

-       lastRxCounter = DMA_BUFFER_SIZE;
-       FpgaSetupSscDma((uint8_t*) dmaBuf, DMA_BUFFER_SIZE);
+       lastRxCounter = ISO14443B_DMA_BUFFER_SIZE;
+       FpgaSetupSscDma((uint8_t*) dmaBuf, ISO14443B_DMA_BUFFER_SIZE);

        uint8_t parity[MAX_PARITY_SIZE];
 
        bool TagIsActive = FALSE;
        uint8_t parity[MAX_PARITY_SIZE];
 
        bool TagIsActive = FALSE;


@@ -1106,7 +1094,7 @@ void RAMFUNC SnoopIso14443b(void)
        // And now we loop, receiving samples.
        for(;;) {
                int behindBy = (lastRxCounter - AT91C_BASE_PDC_SSC->PDC_RCR) &
        // And now we loop, receiving samples.
        for(;;) {
                int behindBy = (lastRxCounter - AT91C_BASE_PDC_SSC->PDC_RCR) &

-                                                               (DMA_BUFFER_SIZE-1);
+                                                               (ISO14443B_DMA_BUFFER_SIZE-1);

                if(behindBy > maxBehindBy) {
                        maxBehindBy = behindBy;
                }
                if(behindBy > maxBehindBy) {
                        maxBehindBy = behindBy;
                }


@@ -1117,13 +1105,13 @@ void RAMFUNC SnoopIso14443b(void)
                cq = upTo[1];
                upTo += 2;
                lastRxCounter -= 2;
                cq = upTo[1];
                upTo += 2;
                lastRxCounter -= 2;

-               if(upTo >= dmaBuf + DMA_BUFFER_SIZE) {
+               if(upTo >= dmaBuf + ISO14443B_DMA_BUFFER_SIZE) {

                        upTo = dmaBuf;
                        upTo = dmaBuf;

-                       lastRxCounter += DMA_BUFFER_SIZE;
+                       lastRxCounter += ISO14443B_DMA_BUFFER_SIZE;

                        AT91C_BASE_PDC_SSC->PDC_RNPR = (uint32_t) dmaBuf;
                        AT91C_BASE_PDC_SSC->PDC_RNPR = (uint32_t) dmaBuf;

-                       AT91C_BASE_PDC_SSC->PDC_RNCR = DMA_BUFFER_SIZE;
+                       AT91C_BASE_PDC_SSC->PDC_RNCR = ISO14443B_DMA_BUFFER_SIZE;

                        WDT_HIT();
                        WDT_HIT();

-                       if(behindBy > (9*DMA_BUFFER_SIZE/10)) { // TODO: understand whether we can increase/decrease as we want or not?
+                       if(behindBy > (9*ISO14443B_DMA_BUFFER_SIZE/10)) { // TODO: understand whether we can increase/decrease as we want or not?

                                Dbprintf("blew circular buffer! behindBy=%d", behindBy);
                                break;
                        }
                                Dbprintf("blew circular buffer! behindBy=%d", behindBy);
                                break;
                        }


@@ -1142,7 +1130,6 @@ void RAMFUNC SnoopIso14443b(void)
                if (!TagIsActive) {                                                     // no need to try decoding reader data if the tag is sending
                        if(Handle14443bUartBit(ci & 0x01)) {
                                if(triggered && tracing) {
                if (!TagIsActive) {                                                     // no need to try decoding reader data if the tag is sending
                        if(Handle14443bUartBit(ci & 0x01)) {
                                if(triggered && tracing) {

-                                       //GetParity(Uart.output, Uart.byteCnt, parity);

                                        LogTrace(Uart.output, Uart.byteCnt, samples, samples, parity, TRUE);
                                }
                                /* And ready to receive another command. */
                                        LogTrace(Uart.output, Uart.byteCnt, samples, samples, parity, TRUE);
                                }
                                /* And ready to receive another command. */


@@ -1153,7 +1140,6 @@ void RAMFUNC SnoopIso14443b(void)
                        }
                        if(Handle14443bUartBit(cq & 0x01)) {
                                if(triggered && tracing) {
                        }
                        if(Handle14443bUartBit(cq & 0x01)) {
                                if(triggered && tracing) {

-                                       //GetParity(Uart.output, Uart.byteCnt, parity);

                                        LogTrace(Uart.output, Uart.byteCnt, samples, samples, parity, TRUE);
                                }
                                /* And ready to receive another command. */
                                        LogTrace(Uart.output, Uart.byteCnt, samples, samples, parity, TRUE);
                                }
                                /* And ready to receive another command. */


@@ -1172,7 +1158,6 @@ void RAMFUNC SnoopIso14443b(void)
                                if(tracing)
                                {
                                        uint8_t parity[MAX_PARITY_SIZE];
                                if(tracing)
                                {
                                        uint8_t parity[MAX_PARITY_SIZE];

-                                       //GetParity(Demod.output, Demod.len, parity);

                                        LogTrace(Demod.output, Demod.len, samples, samples, parity, FALSE);
                                }
                                triggered = TRUE;
                                        LogTrace(Demod.output, Demod.len, samples, samples, parity, FALSE);
                                }
                                triggered = TRUE;


@@ -1217,22 +1202,6 @@ void SendRawCommand14443B(uint32_t datalen, uint32_t recv, uint8_t powerfield, u
 
        set_tracing(TRUE);
        
 
        set_tracing(TRUE);
        

-/*     if(!powerfield) {
-               // Make sure that we start from off, since the tags are stateful;
-               // confusing things will happen if we don't reset them between reads.
-               FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
-               LED_D_OFF();
-               SpinDelay(200);
-       }
- */
-
-       // if(!GETBIT(GPIO_LED_D))      {       // if field is off
-               // FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_READER_RX_XCORR | FPGA_HF_READER_RX_XCORR_848_KHZ);
-               // // Signal field is on with the appropriate LED
-               // LED_D_ON();
-               // SpinDelay(200);
-       // }
-

        CodeAndTransmit14443bAsReader(data, datalen);
 
        if(recv) {
        CodeAndTransmit14443bAsReader(data, datalen);
 
        if(recv) {

diff --git a/fpga/fpga_hf.bit b/fpga/fpga_hf.bit
index a4d72e373bb59cfa56cc3869b1ccb3c18908250a..50c7eef97c8b98461b7d8be9e4e643dd85910241 100644 (file)
Binary files a/fpga/fpga_hf.bit and b/fpga/fpga_hf.bit differ

diff --git a/fpga/hi_read_rx_xcorr.v b/fpga/hi_read_rx_xcorr.v
index f816199e94d8d6c0f4f87dcd60cecb9742f80d1a..afaf7cb6fb17ae0a1f5687a9b48601ead3d65c23 100644 (file)
--- a/fpga/hi_read_rx_xcorr.v
+++ b/fpga/hi_read_rx_xcorr.v
@@ -88,7 +88,7 @@ begin
     // These are the correlators: we correlate against in-phase and quadrature
     // versions of our reference signal, and keep the (signed) result to
     // send out later over the SSP.
     // These are the correlators: we correlate against in-phase and quadrature
     // versions of our reference signal, and keep the (signed) result to
     // send out later over the SSP.

-    if(corr_i_cnt == 7'd0)
+    if(corr_i_cnt == 6'd0)

     begin
         if(snoop)
         begin
     begin
         if(snoop)
         begin


@@ -123,7 +123,7 @@ begin
 
     // The logic in hi_simulate.v reports 4 samples per bit. We report two
     // (I, Q) pairs per bit, so we should do 2 samples per pair.
 
     // The logic in hi_simulate.v reports 4 samples per bit. We report two
     // (I, Q) pairs per bit, so we should do 2 samples per pair.

-    if(corr_i_cnt == 6'd31)
+    if(corr_i_cnt == 6'd32)

         after_hysteresis_prev <= after_hysteresis;
 
     // Then the result from last time is serialized and send out to the ARM.
         after_hysteresis_prev <= after_hysteresis;
 
     // Then the result from last time is serialized and send out to the ARM.