fixing iso14443b (issue #103): fix timing issue (speeding up

the decoders)

diff --git a/armsrc/iso14443b.c b/armsrc/iso14443b.c
index d659558672f2a2a3c7901560744942a23dd7c64c..4e40bb6882a46f5965a6ffd86102417378530d90 100644 (file)
--- a/armsrc/iso14443b.c
+++ b/armsrc/iso14443b.c
@@ -210,7 +210,6 @@ static int Handle14443UartBit(int bit)
                                Uart.bitCnt = 0;
                                Uart.shiftReg = 0;
                                Uart.state = STATE_RECEIVING_DATA;
-                               LED_A_ON(); // Indicate we're receiving
                        }
                        break;
 
@@ -263,6 +262,7 @@ static int Handle14443UartBit(int bit)
                        Uart.posCnt++;
                        if(Uart.posCnt > 10) {
                                Uart.state = STATE_UNSYNCD;
+                               LED_A_OFF();
                        }
                        break;
 
@@ -271,8 +271,6 @@ static int Handle14443UartBit(int bit)
                        break;
        }
 
-       if (Uart.state == STATE_UNSYNCD) LED_A_OFF();
-
        return FALSE;
 }
 
@@ -548,6 +546,7 @@ static RAMFUNC int Handle14443SamplesDemod(int ci, int cq)
                        } else {
                                if(Demod.posCount > 100) {
                                        Demod.state = DEMOD_UNSYNCD;
+                                       LED_C_OFF();
                                }
                        }
                        Demod.posCount++;
@@ -558,6 +557,7 @@ static RAMFUNC int Handle14443SamplesDemod(int ci, int cq)
                        if(v > 0) {
                                if(Demod.posCount > 10) {
                                        Demod.state = DEMOD_UNSYNCD;
+                                       LED_C_OFF();
                                }
                        } else {
                                Demod.bitCount = 0;
@@ -596,13 +596,13 @@ static RAMFUNC int Handle14443SamplesDemod(int ci, int cq)
                                                Demod.output[Demod.len] = b;
                                                Demod.len++;
                                                Demod.state = DEMOD_AWAITING_START_BIT;
-                                       } else if(s == 0x000) {
-                                               // This is EOF
-                                               LED_C_OFF();
-                                               Demod.state = DEMOD_UNSYNCD;
-                                               return TRUE;
                                        } else {
                                                Demod.state = DEMOD_UNSYNCD;
+                                               LED_C_OFF();
+                                               if(s == 0x000) {
+                                                       // This is EOF
+                                                       return TRUE;
+                                               }
                                        }
                                }
                                Demod.posCount = 0;
@@ -611,10 +611,10 @@ static RAMFUNC int Handle14443SamplesDemod(int ci, int cq)
 
                default:
                        Demod.state = DEMOD_UNSYNCD;
+                       LED_C_OFF();
                        break;
        }
 
-       if (Demod.state == DEMOD_UNSYNCD) LED_C_OFF(); // Not synchronized...
        return FALSE;
 }
 
@@ -1168,14 +1168,14 @@ void RAMFUNC SnoopIso14443(void)
                }
 
                if(!ReaderIsActive) {                                           // no need to try decoding tag data if the reader is sending - and we cannot afford the time
-                       if(Handle14443SamplesDemod(ci, cq)) {
+                       if(Handle14443SamplesDemod(ci & 0xFE, cq & 0xFE)) {
 
                                //Use samples as a time measurement
                                if(tracing)
                                {
                                        uint8_t parity[MAX_PARITY_SIZE];
                                        GetParity(Demod.output, Demod.len, parity);
-                                       LogTrace(Demod.output, Demod.len,samples, samples, parity, FALSE);
+                                       LogTrace(Demod.output, Demod.len, samples, samples, parity, FALSE);
                                }
                                triggered = TRUE;
                                LED_A_OFF();

diff --git a/fpga/hi_read_rx_xcorr.v b/fpga/hi_read_rx_xcorr.v
index ec6583b273f0910acb8fe58b59b5857291123ac3..06142637bc2573bb5138a1f922e88675c4380fcc 100644 (file)
--- a/fpga/hi_read_rx_xcorr.v
+++ b/fpga/hi_read_rx_xcorr.v
@@ -171,7 +171,9 @@ begin
         end
     end
 
-    if(corr_i_cnt[5:2] == 4'b000 || corr_i_cnt[5:2] == 4'b1000)
+       // set ssp_frame signal for corr_i_cnt = 0..3 and corr_i_cnt = 32..35
+       // (two frames with 8 Bits each)
+    if(corr_i_cnt[5:2] == 4'b0000 || corr_i_cnt[5:2] == 4'b1000)
         ssp_frame = 1'b1;
     else
         ssp_frame = 1'b0;