mDot
/
Find_one_wire_IDs_2
Important changes to repositories hosted on mbed.com
Mbed hosted mercurial repositories are deprecated and are due to be permanently deleted in July 2026.
To keep a copy of this software download the repository Zip archive or clone locally using Mercurial.
It is also possible to export all your personal repositories from the account settings page.
Dependencies: mbed
Diff: crc8.cpp
- Revision:
- 0:486c7ab9114b
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/crc8.cpp Mon Jun 05 21:11:32 2017 +0000
@@ -0,0 +1,39 @@
+#include <inttypes.h>
+
+#define CRC8INIT 0x00
+#define CRC8POLY 0x18 //0X18 = X^8+X^5+X^4+X^0
+
+uint8_t crc8 ( uint8_t *data_in, uint16_t number_of_bytes_to_read )
+{
+ uint8_t crc;
+ uint16_t loop_count;
+ uint8_t bit_counter;
+ uint8_t data;
+ uint8_t feedback_bit;
+
+ crc = CRC8INIT;
+
+ for (loop_count = 0; loop_count != number_of_bytes_to_read; loop_count++)
+ {
+ data = data_in[loop_count];
+
+ bit_counter = 8;
+ do {
+ feedback_bit = (crc ^ data) & 0x01;
+
+ if ( feedback_bit == 0x01 ) {
+ crc = crc ^ CRC8POLY;
+ }
+ crc = (crc >> 1) & 0x7F;
+ if ( feedback_bit == 0x01 ) {
+ crc = crc | 0x80;
+ }
+
+ data = data >> 1;
+ bit_counter--;
+
+ } while (bit_counter > 0);
+ }
+
+ return crc;
+}