Help me convert this, its easy!!

[Xcoder]

hello all, I need to convert this code to VB6, could anybody please help me!

its this function:

#define BITS_PER_CHAR  8
unsigned short updcrc (unsigned short ch, unsigned short crc)
{
          register short counter = BITS_PER_CHAR;
          register short temp = crc
          while (--counter >= 0)
             if (temp & 0x8000){
          temp <<= 1;
          temp += (((ch <<= 1) & 0x0100) != 0);
          temp ^= 0x1021;
             }
           else{
          temp <<= 1;
          temp += (((ch <<= 1) & 0x0100) != 0);
             }
return (temp);

that calls this one:

#define BITS_PER_CHAR  8
unsigned short updcrc (unsigned short ch, unsigned short crc)
{
          register short counter = BITS_PER_CHAR;
          register short temp = crc
          while (--counter >= 0)
             if (temp & 0x8000){
          temp <<= 1;
          temp += (((ch <<= 1) & 0x0100) != 0);
          temp ^= 0x1021;
             }
           else{
          temp <<= 1;
          temp += (((ch <<= 1) & 0x0100) != 0);
             }
return (temp);

[abcdefg]

Thats not easy I know some vb and i wouldnt know where to start. VB doesnt give u low level access to register variables or addresses. Thats why its harder than u think and VB sucks.

[SLH]

Perhaps if you described what they are doing people will be able to come up with a solution.

[Technocrat]

Its the crc check of smart tags for a SmartPass system. I dont think VB is going to let you do this. You are better off making this a DLL and linking it into your VB program.

[azteched]

There's no problem doing this in VB, VB has bitwise AND, OR, XOR, and you can simulate bitshifting using multiplication or division. I'm feeling under the weather this morning, if this isn't resolved I'll do some code later.

[CornedBee]

It's possible, but CRC checks are supposed to be very fast, and that's something VB isn't good at, esp. if you emulate the shifts.

The DLL is the best approach.

[dis1411]

Originally posted by SLH
Perhaps if you described what they are doing people will be able to come up with a solution.

i think if he could describe what's going on he would be able to convert it to vb himseld