*** M E M O R U M ***

It is the end of an era, I had a quick look at stocks when I heard that news. I decided there was no cause for panic, surprisingly, I don't actually have that many Z80 systems. Thamks to a donation from Les a few years back, the spares work out at 2 CMOS Z80s for each real Z80 system, (MTX, ZX81, Sp...

Sounds like you're building something like : https://www.mtxworld.dk/memorum/viewtopic.php?p=3299#p3299 Writing Z80 code to run with no working ram needs a few "tricks" so while I've posted the early versions to show how it's done. I refrained from publising the final code. So disassemblin...

Answers in order: Build 234, no copies of that source remain. Build 245, the source for that is on the Raspberry Pi Z80 dev system here somwhere. However, it needed a purpose written assembler to build. All the tricks and tweaks needed to run with no ram were written into the assembler as multibye a...

The bright yellow labels are a bit subtle I guess .... True, but you mad tinkerers stick labels on anything and everything :lol: [has a quick check of the Dev MTX] There's only 6 labled chips: The 3 system ROMs The motherboard PAL replacement, currently the MTX500 GAL is fitted, there's a MTX512 ve...

gunrock wrote: ↑05 Mar 2024 15:54

Martin A wrote: ↑05 Mar 2024 12:21 * did you notce the non standard roms on the MTX ?

I did not. That photo was too indistinct and my eyes grow dim...

The bright yellow labels are a bit subtle I guess ....

You haven't a hope in hell of getting the case back together? Absolutely not. That's where the PS2 keyboard interfacre really comes in to it's own :) That MTX is one Memotech altered in the factory to use eprom instead of mask rom. So I have an alternate set of eproms fitted** that has the keyboard...

It is indeed a larger FPGA, it's a Cyclone 4 device EP4C6E which has 30k of onboard ram. That's compared to 13k ram on the Cyclone 2 EP2C5. The original build MFX used the internal ram for the 80 column board memory, plus buffers for the sprite rendering on the VDP. The external chip was used for th...

See anything different about the MFX board in the photos?

I'll give him a poke on your behalf too

Send Dave an e-mail using the link at the bottom of http://primrosebank.net/computers/mtx/p ... _order.htm

The page seems to suggest there are boards available from the last batch I built for him