exxos's Atari, Amiga & retro forum

stephen_usher wrote: 12 Jun 2021 15:53 Yeah. It's always good to check. Maybe check what signals the RAM chip is getting from the ULA whilst you have the socket there and maybe buzz out the data path to the ULA. (Being paranoid.)

I already checked cas/ras and they were there, as was power. I may have also checked the address pins, but my memory escapes me. It often does these days.......

I need to try and make up a pinout diagram for the ULA as the pins, other than 1 on my glop top soldered in model, are not at all clear. I only know where pin 49 is as I checked the 16Mhz clock there.

:dualthumbup:

What sort of memory does it use? 4x 4164 with multiplexing in the ULA?

stephen_usher wrote: 12 Jun 2021 16:50 :dualthumbup:

What sort of memory does it use? 4x 4164 with multiplexing in the ULA?

4x4864 or equivalent.

Ah, so yes, 4164s. (HM4864 is the Hitachi designation. Same pin-out and functionality to the 4164.)

stephen_usher wrote: 12 Jun 2021 18:32 Ah, so yes, 4164s. (HM4864 is the Hitachi designation. Same pin-out and functionality to the 4164.)

And the OKI MSM3764 which is what I have coming. I probably have 4164s kicking around, but guess what? They are in storage....

My plan for Sunday afternoon take out my Electron from storage and play some Citadel!

arkadiusz.makarenko wrote: 12 Jun 2021 21:31 My plan for Sunday afternoon take out my Electron from storage and play some Citadel!

Had my BBC B out getting the hang of Mr Morleys 64K EEPROM adapter, nice and easy to use and I'll be ordering his sideways 32KB ROM/RAM adapter next.

Have fun with your Electron :)

No sign of that memory chip yet then?

stephen_usher wrote: 14 Jun 2021 20:27 No sign of that memory chip yet then?

Sadly not :(

Delivery is showing as Wednesday, but is one of those daft untrackable Post Office numbers that only show collection and delivery, but nothing in between.

Oh. That's annoying. In my experience they generally turn up a day earlier than the estimate, so probably tomorrow.