MEMOTECH MEMOPAK 16K [Wiring diagram]

[sP1d3r]

I think that leaving a Memotech case attached affects the connector after some time, if you look at this picture of the connector before I repaired it, the bottom row of pins wouldn't contact the edge connector.

Bottom row connector pins pushed down

I pushed them back out but I don't know how many times this could be done.

[sP1d3r]

I was able to dump the PROM for this 16K Memopak using my Retro Chip Tester Pro, using the 7488/188/288 32x8 setting.
I don't know if it's the same as the 32K Memopak PROM, the only visible difference between a 16K and a 32K Memopak that I could see from pictures is that the RAM chips are the same as Spectrum upper RAM chips.
Considering that the same PCB is used, it could conceivably be the same PROM.
How would I upload the PROM dump, a .bin file of 1Kb?

A pic of the soldering tool I used to poke out the edge connector pins

Tool for bending out connector pins

[1024MAK]

Upload as a zip file

Mark

[sP1d3r]

Thanks, Mark.

The filename is the CRC-32 as calculated by my Retro Chip Tester Pro.

8a8f4b5e.zip

(185 Bytes) Downloaded 292 times

[sP1d3r]

I've tested the ram pack and it works. I fitted a small 1A Recom DC-DC converter and so far so good.

Working RAM pack

Is there a hi-res mod for a 16K Memopak?

[Lardo Boffin]

Photos of a 32K RAM pack:

[XavSnap]

Thanks Lardo Boffin and Spider for this pictures.

[sP1d3r]

Lardo's pictures are an MT05-01 motherboard but 16K configuration.
A 32K RAM pack has faulty 64K chips, not 16K.

[sP1d3r]

I've repaired Lardo's MT05-01 PCB, it turned out to be a faulty memory chip.
I socketed the chips so that should some suitable chips for a 32K conversion come along, I could swap them.

Faulty HM4816-7 DRAM

I've seen OKI 3732 chips in issue 2 Spectrums, similar to the MSM 3732 chips I've seen in 32K Memopaks.

I've no idea about the 32K Memopak PROM as I haven't one to compare to.

[David G]

Out of curiosity, what is the PROM used for in a RAM pack?