UNIVERSAL ST/F/M 4MB RAM MMU ADAPTER

[lrodriguezrullan]

I am having trouble with this kit. I am getting a black screen on my 1040 STF.

I did check that every pin on the cable is connected to a pin on the shifter board. It seems to be OK. I lifted the R59, R60, R61, R71, R72, and R73 resistors and connected them to 5V.

[exxos]

Please post a image of it all..

[DoG]

Should be R60, R61 for bank 1 and R71, R72 for bank 2 to be disabled. But it all depends on motherboard revisions.

EDIT: Hmm, checked exxos blogpost about fitting the 4MB expansion and you have done what he has done so I don't know. According to Marpet/Frontier board you leave out R59 and R73.

[exxos]

We need a image of what he has and done.

http://www.exxosforum.co.uk/atari/last/4MBMMU/index.htm

As resistor numbers and even orientation of the MMU can be different across motherboard revisions.

[lrodriguezrullan]

Please find some photos of what I did.

[exxos]

Do you have higher resolution images you can send me in PM ? ( you may need to zip them if large images wont upload)

[lrodriguezrullan]

I don't have better photos right now. I will have to retake them.

[lrodriguezrullan]

Is there something that you are looking for that I can clarify, while I retake the photos? Thanks.

[exxos]

Is there something that you are looking for that I can clarify, while I retake the photos? Thanks.

1st and 4th image...

It looks connected up right, but cant tell much else form the images currently.

[lrodriguezrullan]

I just sent you the higher resolution images via private message.

I wasn't sure about my soldering, so I used a multitester to test continuity from each pin in the ribbon cable to the shifter socket. The results are as follows:

Cable 1 -> Socket 32
Cable 2 -> Socket 33
Cable 3 -> Socket 34
Cable 4 -> Socket 35
Cable 5 -> Socket 36
Cable 6 -> Socket 37
Cable 7 -> Socket 38
Cable 8 -> Socket 39
Cable 9 -> Socket 30
Cable 10 -> Socket 29
Cable 11 -> Socket 28
Cable 12 -> Socket 27
Cable 13 -> Socket 26
Cable 14 -> Socket 25
Cable 15 -> Socket 24
Cable 16 -> Socket 23

That is assuming that the cable pins are numbered 1 to 16 from left to right and that the socket pins are numbered from 1 to 40 counter clockwise starting with the bottom left corner of the socket.

Does this look correct?