-    if(active || active_select)
-    {
-        c.arg[0] |= ISO14A_CONNECT;
-        if(active)
-            c.arg[0] |= ISO14A_NO_SELECT;
-    }
+       if(crc && datalen>0 && datalen<sizeof(data)-2)
+       {
+               uint8_t first, second;
+               if (topazmode) {
+                       ComputeCrc14443(CRC_14443_B, data, datalen, &first, &second);
+               } else {
+                       ComputeCrc14443(CRC_14443_A, data, datalen, &first, &second);
+               }
+               data[datalen++] = first;
+               data[datalen++] = second;
+       }
+
+       if(active || active_select)
+       {
+               c.arg[0] |= ISO14A_CONNECT;
+               if(active)
+                       c.arg[0] |= ISO14A_NO_SELECT;
+       }