The Sinclair QL Forum

Fitted Memory and on first boot Minerva still reported 128KB total memory, so does seem to be a 0KB version

On subsequent boots the QL wouldn't start with the card installed so will have to strip out memory chips and re-test without them to see if it still works

Does anyone know if the 0KB card should work in conjunction with other memory expansions or whether it only works with a 128KB QL please?

Many thanks

Solved the problem with the card (helps if you plug it into the QL completely...) but memory not recognised

I guess I join the list of people looking for a 256kb PAL!

Still intrigued as to whether the card should work with other memory expansions though? please

Many thanks

Could anyone give me any idea what I need to read a PAL and duplicate it using an equivalent GAL please?

EDIT: or just to read and write to new PAL's

(I only have a GQ-4X V4 and I’m pretty sure that can’t do it)

Many thanks

Also, is the IC marked "DMPAL16R4ANC" the "PAL" in question please? EDIT: Yes it is

The 16Kb ROM on the board is an MBM27128-25, but I assume this is just a normal EPROM? EDIT: Yes it is

I do now have a PCML Q+ with working 256kb RAM on-board, but would like to try and get my original 0kb board working

Many thanks

Just read both EPROM's and they are identical so there's no code in there specific to 0k vs 256k at least

From what I can see programmers for something like this are £1k+

Am going to call it quits and strip out the memory chips I added to the 0kb board and just keep them as separate 0k and 256k versions

(Maybe I’ll come across a broken board in the future I can get a suitable PAL from)

Hi

I have a PCML board that only the Floppy Disk controller works.

I had assumed the PAL responsible for the Memory expansion mapping was faulty, I thought there was a fix for this, but I will have to look at my old records.

Derek_Stewart wrote: Thu Feb 20, 2025 7:34 am Hi

I have a PCML board that only the Floppy Disk controller works.

I had assumed the PAL responsible for the Memory expansion mapping was faulty, I thought there was a fix for this, but I will have to look at my old records.

From what I've read elsewhere on here there are different PAL's for 0k & 256k (and in a document on dilwyn's site about different interfaces I think)

If there is another way that would be great please

Thanks

Was looking at the DuPal GitHub (for brute force reading the PAL) but I wouldn’t know how to even go about getting a PCB made

I just realised that the Q+ is emulated in MAME (uses identical v1.14 ROM too)

Not knowing anything about MAME, I had hoped someone had emulated (read) the PAL data but there's no sign of a file for that as far as I can see

But surely to emulate the Q+ (unless it really only emulates the 0k version) they'd have to also emulate the PAL in some way?

EDIT: seems MAME doesn’t emulate PALs

Sorry for the ramblings