mbed_example
/
CRC_eample_sd
CRC example for SD driver
main.cpp
- Committer:
- deepikabhavnani
- Date:
- 2018-03-23
- Revision:
- 2:ee110889fa99
- Parent:
- 1:ca0b1e353dfe
- Child:
- 3:97e3e51ca5d5
File content as of revision 2:ee110889fa99:
#include "mbed.h" int crc_sd_7bit() { MbedCRC<POLY_7BIT_SD, 7> ct; char test[5]; uint32_t crc; test[0] = 0x40; test[1] = 0x00; test[2] = 0x00; test[3] = 0x00; test[4] = 0x00; ct.compute((void *)test, 5, &crc); // CRC 7-bit as 8-bit data crc = (crc | 0x01) & 0xFF; printf("The CRC of 0x%x \"CMD0\" is \"0x95\" Result: 0x%x\n", ct.get_polynomial(), crc); test[0] = 0x48; test[1] = 0x00; test[2] = 0x00; test[3] = 0x01; test[4] = 0xAA; ct.compute((void *)test, 5, &crc); // CRC 7-bit as 8-bit data crc = (crc | 0x01) & 0xFF; printf("The CRC of 0x%x \"CMD8\" is \"0x87\" Result: 0x%x\n", ct.get_polynomial(), crc); test[0] = 0x51; test[1] = 0x00; test[2] = 0x00; test[3] = 0x00; test[4] = 0x00; ct.compute((void *)test, 5, &crc); // CRC 7-bit as 8-bit data crc = (crc | 0x01) & 0xFF; printf("The CRC of 0x%x \"CMD17\" is \"0x55\" Result: 0x%x\n", ct.get_polynomial(), crc); return 0; } int crc_sd_16bit() { char test[512]; uint32_t crc; MbedCRC<POLY_16BIT_CCITT, 16> sd(0, 0, false, false); memset(test, 0xFF, 512); // 512 bytes with 0xFF data --> CRC16 = 0x7FA1 sd.compute((void *)test, 512, &crc); printf("16BIT SD CRC (512 bytes 0xFF) is \"0x7FA1\" Result: 0x%x\n", crc); return 0; } int main() { crc_sd_16bit(); crc_sd_7bit(); return 0; }