Questions about STFM 4MB MMU upgrade

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danboid
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Questions about STFM 4MB MMU upgrade

Post by danboid »

I have installed the 4MB MMU upgrade to my STFM but my machine isn't booting atm, I just get a black screen with a white border.

I got someone much more experienced at soldering than me to remove the RAM chips and I clipped the legs of all the RAM caps. I did initially also ask him to try installing the 4 MB upgrade and he ended up installing some 68 Ohm resistors into R71, R72 and R73. I didn't ask him to do that, is that right?

Resistors! Several questions here.

I think I made the mistake of telling him to look at both this page:

https://exxosforum.co.uk/atari/last/4mb/index.htm

and also this page:

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

Obviously the latter is the actual instructions but it seems the MMU page doesn't mention any need for installing or removing any resistors yet the former page says:

"If you only have 512K memory, then you will need to fit the 1MB address line resistors which are normally 68R and 33R."

Could someone please explain this better for me? I need to fit what size resistors where? Or does this not apply to the MMU upgrade?

The same page also says:

"If your STFM has the blue capacitor C49 fitted, this needs to be removed. The capacitors new location will be shown later on."

I can't find the picture it seems to be referring to. Where is C49 on my STFM? I have found, you can't miss, C149 so maybe C49 was a typo? I've not found the schematics for my board yet. Do I also need to remove C(1)49 when doing the MMU upgrade or is this only for that other type of RAM upgrade? I presume so because its not mentioned on the MMU page.

Another two points regarding the MMU. I had to remove a metal clip that was covering my MMU before I could attach the memory upgrade but no mention was made of having to or how best to remove this clip on the 4MB MMU upgrade page. It was easy to remove but I it would've been nice to have this covered and it would've made us less nervous about removing it.

And last but not least, I know you might think I'm silly for suggesting this but the MMU upgrade doesn't actually specifically say whether the user has to remove the MMU or not, well at least I thought there was still some scope for someone to think that might be required.

It would be good if it said something like "After removing the metal clip that may be covering your MMU (like so...) the MMU must remain in the socket before clipping the MMU 4 MB RAM upgrade over the MMU." I'm not sure its totally clear from the current MMU page pics ad text that the MMU is still in the socket in your photos on that page.

IMG_20240813_103405.jpg
STFM-MMU-4MB-nopescreen.jpg
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The 'Uzebox Omega is a fully open source games console that you can build in a weekend, even with no previous electronics experience:

https://uzebox.org/wiki/Omega
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exxos
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Re: Questions about STFM 4MB MMU upgrade

Post by exxos »

The MMU ribbon clip doesn't look clipped in properly and I can't work out if you have pin 1 on the MMU board to pin 1 on the MMU ? From what I can tell its not and in backwards ?

2021a.jpg

Or if you have a older version the numbers are on the PCB to align with the MMU.

mmu3.jpg

See STEP 2 of the fitting instructions.

https://exxosforum.co.uk/atari/last/4MBMMU/index.htm
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rubber_jonnie
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Re: Questions about STFM 4MB MMU upgrade

Post by rubber_jonnie »

As @exxos mentioned, the MMU adapter cable isn't locked in properly. A black screen/white border generally means no RAM.

In addition, and it isn't possible to tell from the photo, that model of mainboard has the MMU rotated 180 degress to normal, and from what I can see of the same board I have here, pin 1 is on the right hand side of the MMU and is numbered '1', so your MMU adapter is probably 180 degrees out and needs to be rotated to match pin 1 of the MMU.

You need to check these things and also that the MMU adapter is fully inserted before trying again.
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danboid
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Re: Questions about STFM 4MB MMU upgrade

Post by danboid »

Yes, as exxos correctly spotted, I had inserted the MMU board back to front. :lol:

I've literally only ran sysinfo for a couple of minutes on it so far but it is booting now and I seem to have 4 MB RAM now after putting it in the right way :D

What resistors, if any, should I have in R71, R72 and R73 to use 4 MB on my STFM revision? My current config seems to be OK.
STFM-4MB-right.jpg

STFM-MMU-4MB-yepscreen.jpg

Should I be able to use my Sidecart with TOS 1.0.2 or will I have to wait for my EEPROMS / 1.0.4 to use the sidecart? I'll find out soon enough.
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The 'Uzebox Omega is a fully open source games console that you can build in a weekend, even with no previous electronics experience:

https://uzebox.org/wiki/Omega
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Re: Questions about STFM 4MB MMU upgrade

Post by exxos »

danboid wrote: 13 Aug 2024 12:39 What resistors, if any, should I have in R71, R72 and R73 to use 4 MB on my STFM revision? My current config seems to be OK.
Those resistors are not important as they are for the old RAM.
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logronoide
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Re: Questions about STFM 4MB MMU upgrade

Post by logronoide »

danboid wrote: 13 Aug 2024 12:39 Should I be able to use my Sidecart with TOS 1.0.2 or will I have to wait for my EEPROMS / 1.0.4 to use the sidecart? I'll find out soon enough.
SidecarTridge Multidevice works on any TOS version and EmuTOS (except the floppy disk emulator for version EmuTOS 1.3.0 and it will be fixed in the next firmware release in September).

Actually one of the benefits of Multidevice running GEMDRIVE is it can emulate a hard disk in TOS 1.00 and 1.02.
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danboid
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Re: Questions about STFM 4MB MMU upgrade

Post by danboid »

logronoide wrote: 15 Aug 2024 19:24 SidecarTridge Multidevice works on any TOS version and EmuTOS (except the floppy disk emulator for version EmuTOS 1.3.0 and it will be fixed in the next firmware release in September).

Actually one of the benefits of Multidevice running GEMDRIVE is it can emulate a hard disk in TOS 1.00 and 1.02.
Can we (STFM users at least) ony boot the 128 Kb ROM version of EmuTOS via sidecart?

It doesn't look like EmuTOS 1.3 can see my sidecart virtual c: drive:

https://github.com/sidecartridge/ataris ... issues/127
The 'Uzebox Omega is a fully open source games console that you can build in a weekend, even with no previous electronics experience:

https://uzebox.org/wiki/Omega
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logronoide
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Re: Questions about STFM 4MB MMU upgrade

Post by logronoide »

danboid wrote: 15 Aug 2024 20:30
logronoide wrote: 15 Aug 2024 19:24 SidecarTridge Multidevice works on any TOS version and EmuTOS (except the floppy disk emulator for version EmuTOS 1.3.0 and it will be fixed in the next firmware release in September).

Actually one of the benefits of Multidevice running GEMDRIVE is it can emulate a hard disk in TOS 1.00 and 1.02.
Can we (STFM users at least) ony boot the 128 Kb ROM version of EmuTOS via sidecart?

It doesn't look like EmuTOS 1.3 can see my sidecart virtual c: drive

https://github.com/sidecartridge/ataris ... issues/127
EDITED:
EmuTOS versions 1.2.1 and 1.3.0 are available, and I can confirm that EmuTOS 1.3.1 has the ACSI driver. I could boot the computer with the EmuTOS 1.3.1 128KB in ROM emulation mode with an ACSI2STM disk drive connected. After booting, it starts the EmuCON2 command line tool from drive C:\

I ran some programs and games successfully from the command line. Applications without the GEM.
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danboid
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Re: Questions about STFM 4MB MMU upgrade

Post by danboid »

logronoide wrote: 15 Aug 2024 21:36
danboid wrote: 15 Aug 2024 20:30

Can we (STFM users at least) ony boot the 128 Kb ROM version of EmuTOS via sidecart?

It doesn't look like EmuTOS 1.3 can see my sidecart virtual c: drive

https://github.com/sidecartridge/ataris ... issues/127
EDITED:
EmuTOS versions 1.2.1 and 1.3.0 are available, and I can confirm that EmuTOS 1.3.1 has the ACSI driver. I could boot the computer with the EmuTOS 1.3.1 128KB in ROM emulation mode with an ACSI2STM disk drive connected. After booting, it starts the EmuCON2 command line tool from drive C:\

I ran some programs and games successfully from the command line. Applications without the GEM.
Oh great! Sounds like I should be able to get FreeMiNT / ST Mint or whatever to boot then.

You say I need a EmuTOS 1.3.1 128 Kb rom build? Could you add this to the sidecart "roms available via wifi" menu or otherwise could you tell me where where I can download a suitably new EmuTOS build please? You've obviously already built it if its not available for download yet.

I'm going to have to try booting FreeMiNT on my A600 too as I upgraded that to 4MB RAM and I have an IDE to SD card adapter which I hope FreeMiNT will support.

This is getting OT now so we should continue this in another topic, more sidecart related topic.

EDIT

It seems the file I was looking for is called emutos-cartridge... from https://sourceforge.net/projects/emutos ... snapshots/ . I'll give it a go now and then we can discuss it in another topic.
The 'Uzebox Omega is a fully open source games console that you can build in a weekend, even with no previous electronics experience:

https://uzebox.org/wiki/Omega
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danboid
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Joined: 18 Jul 2024 19:25

Re: Questions about STFM 4MB MMU upgrade

Post by danboid »

I have tried booting a recent dev snapshot build of emutos-cartridge on my sidecart but the EmuTOS screen only shows one "A" drive in the drive list, no C drive.

Could I be configuring sidecarts HD incorrectly? I'm hoping to use the sidecart to both emulate a HD and boot emutos from the SD card so what is the correct sequence of actions to do this?

I have been starting sidecarts hd emulation which then tries and fails to boot FreeMiNT, then the enter the sidecart confg menu via power cycling before I load the emutos 1.3.1 rom. Is this not what I'm supposed to be doing here? Is my sidecart hd no longer "mounted" after power cycling my ST?

I presume that any hard drive I configure under the sidecart config menu should remain configured when I load a cartridge rom from the sd cart? I'm relying on that being possible as I don't have a way to burn EmuTOS onto EEPROMs.
The 'Uzebox Omega is a fully open source games console that you can build in a weekend, even with no previous electronics experience:

https://uzebox.org/wiki/Omega

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