Steve, you're showing your age. That fact I know what DTL is suggests mine also! DM936 was a hex inverter if I remember correctly. Which has prompted me to refer to my old National Semi databook from MAY 1971 which makes me 5 years old at that time (I started early). Tri-State was a new thing back then.

Michael - 2114's - they were the bomb. I was still using 2102's with my pmos SC/MP (ins8050- i can still remember some of the opcodes - eek!). Luckily 1702's were still fairly obscure - i got into eproms when they were 2716's. At least they didn't loose the code when you sneezed or didn't sequence the power correctly.

Guys what do you think - I've got a handful of 8048's with 8243 expanders - do you have any hints (and code) on how i can make a GSM mobile with it? With voice recognition and java execution of course.