Further additions to tidemod to differentiate between ro and rw tags and check crc...

[proxmark3-svn] / common / crc16.c

diff --git a/common/crc16.c b/common/crc16.c
new file mode 100644 (file)
index 0000000..6cdf3ea
--- /dev/null
+++ b/common/crc16.c
@@ -0,0 +1,11 @@
+unsigned short update_crc16( WORD crc, BYTE c ) {\r
+       WORD i, v, tcrc = 0;\r
+\r
+       v = (crc ^ c) & 0xff;\r
+  for (i = 0; i < 8; i++) {\r
+      tcrc = ( (tcrc ^ v) & 1 ) ? ( tcrc >> 1 ) ^ 0x8408 : tcrc >> 1;\r
+      v >>= 1;\r
+  }\r
+\r
+  return (crc >> 8) ^ tcrc;\r
+}\r