I belive it is also important to make steady progress rather than trying to think of every enhancement we want and then build it. Just look at the Arcade ICE or RatBox projects if you want to see what that thinking produces. Touche' Kev ;o) Time for an update on (non)progress so far. 1) Trashed idea of using a cpu to generate cpu control signals as this didn't give 'real time' control over the board. So the ICE requires a few configuration parameters (data and address setting, whether its read or write IO or memory) give it a start strobe and it performs 1 complete bus cycle at cpu speed and stops. Adding an onboard CPU would give scope to loop tests at higher speed rather than multiple requests for cycles through the Comms I/F. 2) Now using state machines to 'Accurately' simulate CPU control signals synchronised from UUT cpu clock. Currently have WORKING and tested state machines for Z80 (includes selectable refresh ability) and 6502, 680X are the next in the design pipeline. The prototypes use TTL logic the final version will use an FPGA to make it more compact. 3) Clock(input to cpu socket) speed counter incorporated (I know someone on here was on about that in the past weeks). 4) Re-instating the board files (memory map/ICE config info) that I dropped from ICE Mk1. 5) All other operational features will be incorporated as per the spec page on my now defunct website. 6) It will have RS232 when I get VB6 to talk properly as at the moment it seems to buffer comms data all over the place (anyone who uses VB Comms, any help would be appreciated) or I could just revert to it being parallel port driven again. 7)Disussions where held with various interested parties over the weekend of the last UKVAC meet, Mike Coates being one respondent getting his ear bent. The out come from those talks hasn't changed my hardware design (Hallelujah) but there was a request for a Dissasembler built into the GUI and an Emulator for each CPU so that the board can be 'run' though this would be sort of a single step mode. I see this feature as a 'would be great to have' but it isn't a priority and may get done sometime never. Wow imagine that me using the work priority! When will it be available? Don't ask I'm fitting it inbetween my studies for the MCSE exams in 5 weeks time, after that I should be able to devote plenty of time to it. Thats all for now Chris Arcade ICE (thinker not do'er)