From: Dave McGuire <mcguire at neurotica.com> I built a Z8530-based AX.25 PAD for ham packet radio...but that was 25 years ago! Nice! I remember being thoroughly impressed with the Z8530, and I've used it in several projects since then... I'm pretty !@*^% impressed too (except for the annoying two-step register access, which I guess is fixed in other versions). That DPLL is the perfect thing for ham packet radio -- wish I'd known about that (I paid Real Money for a used DUP11 about 20 years ago hoping to use it for hamming but never got around to building the circuitry it would have taken to whip up a clock, but it seems the Z8530 already has that and was commonly available at the time -- dammit!). So yes...if you're doing sync stuff with it, that might be very handy if we do this and it goes this route. Sync is the plan but I don't yet have anything to test against (waiting for some trivial PCBs to come back that save me the trouble of piecing together a Berg-to-DB25 cable for my DUV11, and I think they'll also work for DMV11s and DUP11s, so I'll have plenty to test/debug with). So that'll change within the next week and I'm working to have code ready by then. I would imagine it'd be offended. ;) However if memory serves, HDLC frames contain a few bits' worth of sequence numbers. BTW is there any particular target in mind for this? If it's for HECnet, DDCMP would probably be more useful than the annoying bit-stuffing protocols. But better yet would be to support everything ... no point in having to build almost the same thing again later. As for config: is using the RS232 port (in async mode) too easy? John Wilson D Bit