The following code example shows the encryption and decryption process using 3DES with and without CBC. The key scheduler is set to populate both key schedules. The results of the operations are stored in the original data array.

#include "msp430xxxx.h"
#include "TI_DES.h"

int main( void )
{  
   des_ctx       dc1; // Key schedule structure
   unsigned char *cp;
   unsigned char data[]   = {0x69, 0xc4, 0xe0, 0xd8, 0x6a, 0x7b, 0x04, 0x30, 0xd8,
                             0xcd, 0xb7, 0x80, 0x70, 0xb4, 0xc5, 0x5a};
   unsigned char key[8]   = {0x00,0x01,0x02,0x03,0x04,0x05,0x06,0x07};
   unsigned char key1[8]  = {0x01,0x23,0x45,0x67,0x89,0xab,0xcd,0xfe};
   unsigned char key2[8]  = {0x01,0x23,0x45,0x67,0x89,0xab,0xdc,0xfe};
   cp = data;

   ///First 8 bytes of Data will be Encrypted then Decrypted
   TripleDES_ENC( &dc, cp, 1, key, key1, key2);   // 3DES Encrypt
   TripleDES_DEC( &dc, cp, 1, key, key1, key2);   // 3DES Decrypt

   /// All 16 Bytes of Data will be Encrypted then Decrypted with CBC
   TripleDES_ENC_CBC( &dc, cp, 2, key, key1, key2); // 3DES Encrypt
   TripleDES_DEC_CBC( &dc, cp, 2, key, key1,  key2); // 3DES Decrypt

return 0;
}