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Creating the PAL​ chips

A project log for ISA bus slave NS32016 processor board

By Dave Rand and George Scolaro, 1985.

keithKeith 02/03/2024 at 20:550 Comments

This is a doddle. Compile using WinCUPL. 

I have plenty of PAL chips and a suitable programmer.

https://hackaday.io/project/160901-antique-pal-reading-system

It is not hard to port the logic to GAL chips. I can program them too. I can program and post these devices to anyone making this board.

The NS DRAM controller uses a support PAL which they stocked under the part number DP84412. It is no longer sold, but  it is simply a programmed PAL16R6A. I have some of these. The logic would fit in a GAL16V8.

Amazingly, the data sheet includes the logic equations! So no problem recreating this part.

However, this may be completely useless without the DP8419 chip which is a multiplexer and high-current driver for the DRAM address lines.

I found 70 are still available, at $320 for 6 units. ($53 each):

https://www.digikey.com/en/products/detail/rochester-electronics-llc/DP8419N-70/11509383

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