Hello to all that responded to my post; "Q: PC/AT Bus Pin-Out, Info/Hints/Tips" Thanks to all of you that replied. I was very happy with the number and quality of the response. I apologize for taking so long to reply, and for the fact that due to time constraints, this is arriving to you in the form of a 'Form Letter'. It has been outragously hectic here, as I am sure it is for all of you. My wife took ill and my business went crazy. Which I suppose is better than the other way around. Although there was that time when she got crazy, and decided that .... well involved whipped cream, anyway ... If ever I can help any of you out, please let me know. I have some 8051 routines as well as some PIC stuff. If I own it, you can have it. If it belongs to someone else, I can give details of the inner workings and how to acheive it, but not the source. I did visit all of the sites that you guys listed. It was all very helpful. I also enjoyed the various suggustions. You all know how to cut thru the B.S. and arrive at a good solution. Thanks again. Brent Pollock ccs@ewol.com Customized Controller Solutions >I highly recommend a book called 'AT Bus Design' by Edward Solari. It is >published by Annabooks. The ISBN # is 0-929392-08-6. It has timing diagrams >and info for 8 and 16 bit ISA, E-ISA and EISA designs. I bought this book >several years ago (it was published in 1990) and have used it quite often to >success. Good luck. >