This version code now reads a TI tag properly.

[proxmark3-svn] / armsrc / appmain.c

diff --git a/armsrc/appmain.c b/armsrc/appmain.c
index 47da5ad50b704c2121531bb1449ad53526fa2a46..a5c082e59e9325cd0ff138d55454063ce3388128 100644 (file)
--- a/armsrc/appmain.c
+++ b/armsrc/appmain.c
@@ -206,23 +206,22 @@ void ModThenAcquireRawAdcSamples125k(int delay_off,int period_0,int period_1,BYT
        DoAcquisition125k(at134khz);
 }
 
-//-----------------------------------------------------------------------------
-// Read a TI-type tag. We assume that the tag has already been illuminated,
-// and that the exciting signal has been turned off. That means that we just
-// acquire the `one-bit DAC' bits from the comparator.
-//-----------------------------------------------------------------------------
 void AcquireTiType(void)
 {
        int i;
-       int n = 4000;
+       int n = 5000;
 
        // clear buffer
        memset(BigBuf,0,sizeof(BigBuf));
 
-  // Set up the synchronous serial port
+       // Set up the synchronous serial port
   PIO_DISABLE = (1<<GPIO_SSC_DIN);
   PIO_PERIPHERAL_A_SEL = (1<<GPIO_SSC_DIN);
 
+       // steal this pin from the SSP and use it to control the modulation
+  PIO_ENABLE = (1<<GPIO_SSC_DOUT);
+       PIO_OUTPUT_ENABLE       = (1<<GPIO_SSC_DOUT);
+
   SSC_CONTROL = SSC_CONTROL_RESET;
   SSC_CONTROL = SSC_CONTROL_RX_ENABLE | SSC_CONTROL_TX_ENABLE;
 
@@ -231,41 +230,52 @@ void AcquireTiType(void)
   SSC_CLOCK_DIVISOR = 12;
 
   SSC_RECEIVE_CLOCK_MODE = SSC_CLOCK_MODE_SELECT(0);
-  SSC_RECEIVE_FRAME_MODE = SSC_FRAME_MODE_BITS_IN_WORD(32) | SSC_FRAME_MODE_MSB_FIRST;
-  SSC_TRANSMIT_CLOCK_MODE = 0;
-  SSC_TRANSMIT_FRAME_MODE = 0;
-
-  i = 0;
-  for(;;) {
-      if(SSC_STATUS & SSC_STATUS_RX_READY) {
-          BigBuf[i] = SSC_RECEIVE_HOLDING;     // store 32 bit values in buffer
-          i++; if(i >= n) return;
-      }
-      WDT_HIT();
-  }
-}
+       SSC_RECEIVE_FRAME_MODE = SSC_FRAME_MODE_BITS_IN_WORD(32) | SSC_FRAME_MODE_MSB_FIRST;
+       SSC_TRANSMIT_CLOCK_MODE = 0;
+       SSC_TRANSMIT_FRAME_MODE = 0;
 
-void AcquireRawBitsTI(void)
-{
        LED_D_ON();
-       // TI tags charge at 134.2Khz
-       FpgaSendCommand(FPGA_CMD_SET_DIVISOR, 88); //134.8Khz
-       FpgaWriteConfWord(FPGA_MAJOR_MODE_LF_READER);
+
+       // modulate antenna
+       PIO_OUTPUT_DATA_SET = (1<<GPIO_SSC_DOUT);
 
        // Charge TI tag for 50ms.
        SpinDelay(50);
+
+       // stop modulating antenna and listen
+       PIO_OUTPUT_DATA_CLEAR = (1<<GPIO_SSC_DOUT);
+
        LED_D_OFF();
 
-       LED_A_ON();
-       // Place FPGA in passthrough mode so as to stop driving the LF coil,
-       // in this mode the CROSS_LO line connects to SSP_DIN
+       i = 0;
+       for(;;) {
+                       if(SSC_STATUS & SSC_STATUS_RX_READY) {
+                                       BigBuf[i] = SSC_RECEIVE_HOLDING;        // store 32 bit values in buffer
+                                       i++; if(i >= n) return;
+                       }
+                       WDT_HIT();
+       }
+
+       // return stolen pin ro SSP
+       PIO_DISABLE = (1<<GPIO_SSC_DOUT);
+       PIO_PERIPHERAL_A_SEL = (1<<GPIO_SSC_DIN) | (1<<GPIO_SSC_DOUT);
+}
+
+void AcquireRawBitsTI(void)
+{
+       LED_D_ON();
+       // 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);
-       LED_A_OFF();
 }
 
 //-----------------------------------------------------------------------------