>         If you want to do either forwared error control (ie receiver can
>detect AND correct) or just a simple receiver detects errors (and then
>either discards or requests re-transmission) you need to be able to locate
>the packet!  This is called framing.  Check out any computer networks text -
>the issue cited above (jumping into the middle of a packet)  is trivially
>solved by framing - look for start-of-frame and discard everything till you
>get one.

Fair enough. However, if you are using a relatively huge (16 bit) CRC on a
relatively small (10 byte) fixed length packet, you can dispense with the
start of frame and end of frame characters and the required "escaping" of
them in the case that your data contains them. Lots of different ways to
skin a cat. All of them fun.



                                Sincerely,
                                Brent A. Crosby

| Brent A. Crosby
| Crystalfontz America, Incorporated
| 15611 East Washington Road
| Valleyford, WA 99036
| voice (509) 291-3514 facsimile (509) 291-3345
| http://www.crystalfontz.com brent@crystalfontz.com