CHG: according to measureement by @wilrn the actual timing for receiving tag data...

diff --git a/armsrc/legicrf.c b/armsrc/legicrf.c
index e8a2e1aab0616f2b9dcb485ebefa85f4a6025fd7..b1378b811e1ac99e4702f4c53d7058c6bc76ac0c 100644 (file)
--- a/armsrc/legicrf.c
+++ b/armsrc/legicrf.c
@@ -89,11 +89,9 @@ static void setup_timer(void) {
 #define FUZZ_EQUAL(value, target, fuzz) ((value) > ((target)-(fuzz)) && (value) < ((target)+(fuzz)))
 
 #ifndef SHORT_COIL
-//#define LOW(x)        AT91C_BASE_PIOA->PIO_CODR = (x)
 # define SHORT_COIL    LOW(GPIO_SSC_DOUT);
 #endif
 #ifndef OPEN_COIL
-//#define HIGH(x)       AT91C_BASE_PIOA->PIO_SODR = (x)
 # define OPEN_COIL     HIGH(GPIO_SSC_DOUT);
 #endif
 
@@ -104,12 +102,13 @@ uint32_t sendFrameStop = 0;
 //    one == 80us / 120ticks
 //    zero == 40us / 60ticks
 #ifndef COIL_PULSE
-# define COIL_PULSE(x)  { \
+# define COIL_PULSE(x) \
+       do { \
                SHORT_COIL; \
-               WaitTicks(RWD_TIME_PAUSE); \
+               WaitTicks( (RWD_TIME_PAUSE) ); \
                OPEN_COIL; \
                WaitTicks((x)); \
-       }
+       } while (0) 
 #endif
 
 // ToDo: define a meaningful maximum size for auth_table. The bigger this is, the lower will be the available memory for traces. 
@@ -282,8 +281,9 @@ static void frame_receiveAsReader(struct legic_frame * const f, uint8_t bits) {
        uint8_t i = bits, edges = 0;    
        uint16_t lsfr = 0;
        uint32_t the_bit = 1, next_bit_at = 0, data;
+       
        int old_level = 0, level = 0;
-
+       
        AT91C_BASE_PIOA->PIO_ODR = GPIO_SSC_DIN;
        AT91C_BASE_PIOA->PIO_PER = GPIO_SSC_DIN;
        
@@ -298,15 +298,15 @@ static void frame_receiveAsReader(struct legic_frame * const f, uint8_t bits) {
        data = lsfr;
        
        //FIXED time between sending frame and now listening frame. 330us
-       //WaitTicks( GET_TICKS - sendFrameStop - TAG_FRAME_WAIT);
-       WaitTicks( 490 );
+       //WaitTicks( TAG_FRAME_WAIT - (GET_TICKS - sendFrameStop ) );
+       WaitTicks( 495 );
 
        uint32_t starttime = GET_TICKS;
-       
        next_bit_at =  GET_TICKS + TAG_BIT_PERIOD;
-       
+
        while ( i-- ){
                edges = 0;
+               uint8_t adjust = 0;
                while  ( GET_TICKS < next_bit_at) {
 
                        level = (AT91C_BASE_PIOA->PIO_PDSR & GPIO_SSC_DIN);
@@ -315,11 +315,17 @@ static void frame_receiveAsReader(struct legic_frame * const f, uint8_t bits) {
                                ++edges;
                        
                        old_level = level;
-               }
+                       
+                       if(edges > 20 && adjust == 0) {
+                               next_bit_at -= 15;
+                               adjust = 1;
+                       }
+               }               
+
                next_bit_at += TAG_BIT_PERIOD;
                
                // We expect 42 edges  == ONE
-               if(edges > 30 && edges < 64)
+               if(edges > 20 && edges < 64)
                        data ^= the_bit;
 
                the_bit <<= 1;  
@@ -351,7 +357,7 @@ static uint32_t setup_phase_reader(uint8_t iv) {
        
        // Switch on carrier and let the tag charge for 1ms
        HIGH(GPIO_SSC_DOUT);
-       WaitUS(300);    
+       WaitUS(1000);   
        
        ResetTicks();
        
@@ -367,8 +373,8 @@ static uint32_t setup_phase_reader(uint8_t iv) {
        frame_receiveAsReader(&current_frame, 6);
 
        // fixed delay before sending ack.
-       WaitTicks(387);  // 244us
-       legic_prng_forward(3);  //240us / 100 == 2.4 iterations
+       WaitTicks(366);  // 244us
+       legic_prng_forward(1);  //240us / 100 == 2.4 iterations
        
        // Send obsfuscated acknowledgment frame.
        // 0x19 = 0x18 MIM22, 0x01 LSB READCMD 
@@ -432,8 +438,8 @@ int legic_read_byte(int byte_index, int cmd_sz) {
        // 460 | 690
        // 258 | 387
        // 244 | 366
-       WaitTicks(332); 
-       legic_prng_forward(2); // 460 / 100 = 4.6  iterations
+       WaitTicks(366); 
+       legic_prng_forward(3); // 460 / 100 = 4.6  iterations
 
        uint8_t byte = 0, crc = 0, calcCrc = 0;
        uint32_t cmd = (byte_index << 1) | LEGIC_READ;