Retro Chip Tester Pro, done!

[Chuck Guzis]

On 2/10/22 09:11, dwight via cctalk wrote:
> I hope you are not thinking it would test an Intel 4004 or a 8008? That would be a stretch. For the 4004, there is only a narrow range of frequencies it runs under. I'm not that familiar with the 8008 but suspect it has similar restrictions. Both use dynamic registers. Both use PMOS voltage levels( 15V ). A 4008 RAM chip is not the same as an intel 4008 chip.
> It is conceivable to use a logic tester to test a i4004 but it would be a lot of effort. Each instruction does unique operations inside of the i4004. One would have to have 256^2 inputs to fully test a i4004 from the pins. Even then there are a similar number of replies that would have to be checked. One could at best have a simple confidence test that it appeared to be working, as most failures of IC cause complete failure of the chip. Even Intel never fully tested parts going out the door. Even for a processor as simple as the 4004, a complete test is not practical. There are not test circuits built into it either.
> Erturk Kolcalar makes a retro processor exerciser. It basically runs through a USB port from a PC. In its current form, it can't fully test a i4004 because it doesn't meet the proper frequency ( some will work but others won't, but still be functional i4004s ). It runs code loaded from the PC. He currently has the code for the Busicom calculator running.
> I don't recall if he has one for the 8008?

Is it safe to assume that the chip tester works with TTL-level signals
only?  So no ECL or PMOS, for example?

--Chuck