X-Git-Url: http://rtime.felk.cvut.cz/gitweb/can-benchmark.git/blobdiff_plain/85663f7d1d874b065a93fc451bacd43bca9fa73c..d2073a52c1ba52749c1c9522c42ccbfc83b70b1d:/latester/latester.c

diff --git a/latester/latester.c b/latester/latester.c
index a5a7c47..b0937ba 100644
--- a/latester/latester.c
+++ b/latester/latester.c
@@ -1,6 +1,6 @@
 /**************************************************************************/
 /* CAN latency tester                                                     */
-/* Copyright (C) 2010, 2011, 2012 Michal Sojka, DCE FEE CTU Prague        */
+/* Copyright (C) 2010, 2011, 2012, 2013 Michal Sojka, DCE FEE CTU Prague  */
 /* License: GPLv2     	     	    	    				  */
 /**************************************************************************/
 
@@ -204,7 +204,7 @@ uint32_t calc_bitmap_crc(uint32_t *bitmap, unsigned start, unsigned end)
     crc = crc_update(crc, bitmap[1], 32);
     crc = crc_update(crc, bitmap[2], end - 64 > 32 ? 32 : end - 64);
     crc = crc_update(crc, bitmap[3], end > 96 ? end - 96 : 0);
-    return (uint32_t)htons(crc) << 17;
+    return (uint32_t)htons(crc << 17);
 }
 
 void write_crc_to_bitmap(uint32_t crc, uint32_t *bitmap, struct can_frame *frame)
@@ -237,6 +237,11 @@ unsigned calc_stuff_bits(struct can_frame *frame) {
 /* 	printf("Frame: %s\n", received); */
 	
 	if (frame->can_id & CAN_EFF_FLAG) {
+		// bit 31                              0
+		// [0] |...........................sBBBB| s = SOF, B = Base ID (11 bits)
+		// [1] |BBBBBBBSIEEEEEEEEEEEEEEEEEER10DLC4| S = SRR, I = IDE, E = Extended ID (18 bits), DLC4 = DLC
+		// [2] |00000000111111112222222233333333| Data bytes, MSB first
+		// [3] |44444444555555556666666677777777|
 		bitmap[0] =
 			((frame->can_id & CAN_EFF_MASK) >> 25);
 		bitmap[1] =
@@ -251,6 +256,10 @@ unsigned calc_stuff_bits(struct can_frame *frame) {
 		start = 27;
 		end = 64 + 8*frame->can_dlc;
 	} else {
+		// bit 31                              0
+		// [0] |.............sIIIIIIIIIIIRE0DLC4| s = SOF, I = ID (11 bits), R = RTR, E = IDE, DLC4 = DLC
+		// [1] |00000000111111112222222233333333| Data bytes, MSB first
+		// [2] |44444444555555556666666677777777|
 		bitmap[0] =
 			(frame->can_id << 7) |
 			(!!(frame->can_id & CAN_RTR_FLAG)) << 6 |