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

2009-07-22 11:39:39 +00:00
parent 1569d97730
commit 0c2ed92d87
3 changed files with 98 additions and 23 deletions
--- a/common/crc16.c
+++ b/common/crc16.c
@@ -0,0 +1,11 @@
+unsigned short update_crc16( WORD crc, BYTE c ) {
+	WORD i, v, tcrc = 0;
+
+	v = (crc ^ c) & 0xff;
+  for (i = 0; i < 8; i++) {
+      tcrc = ( (tcrc ^ v) & 1 ) ? ( tcrc >> 1 ) ^ 0x8408 : tcrc >> 1;
+      v >>= 1;
+  }
+
+  return (crc >> 8) ^ tcrc;
+}