Third Slot for Philips Nms 8250/80

By x1pepe

Expert (86)

x1pepe's picture

30-09-2018, 21:54

Hello everyone. I appeal to you once again to ask you for help.
In this link:

It is explained how to add a third Slot, I know it is a topic that has already been discussed in these forums, but the lack of photos and several things that I do not understand from the text make me not decide to start this project.
Someone from around here who has done it could show me a picture?
Thanks and greetings to all.

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By Wild_Penguin

Hero (542)

Wild_Penguin's picture

01-10-2018, 08:19

Hi x1pepe,

Can you be more specific, which part from the instructions is unclear? That could help in helping =-)

Relevant documentation here is the nms825x slotmap:

Slot 3-1 is "free" which means this subslot can be used for built-in modifications / expansions. Most of the signals are already available at the MY connector, but that is the only thing special about the 825x/80 (many msx machines have an extra SUBslot free, fewer have a main slot free). Whether it makes sense to solder in an actual slot, is debateable IMO (if that is what you had in mind). It will be a subslot in any case. It is more usefull (IMO) for things like built-in DOS or MSX-AUDIO or MSX-MUSIC.

What do you specifically need this slot for?

By x1pepe

Expert (86)

x1pepe's picture

01-10-2018, 08:52

The problem is when I have three cartridges I want to put at the same time: Mith&Dragons, video cartridge V9999, FmPack or similar).
These instructions don't have any draw or photo, so I'm afraid to make bad connections and damage the computer.
Can I Add a extra sosoldering a flat wire? Where?
Some scheme would be of great help. Smile

By sdsnatcher73

Hero (535)

sdsnatcher73's picture

01-10-2018, 23:23

Why not get a slot expander? Don’t know Mith & Dragons or V9999 very well but my guess is they do not use an internal slot expansion (so they should work from a sub slot). FM-PAC can work in a sub slot for sure.

By x1pepe

Expert (86)

x1pepe's picture

02-10-2018, 00:05

The mod "Third slot" its a cool mod always I want to do.
The slot expanders they are hard to find and expensive, I had one but now it doesn't work.