Need help with 2 Final Expansion 3 carts

[CRG(Glen)]

Hello all, I'm Glen, I've had a couple of VIC20s in my collection for a while but done very little with them as I never really had means of loading software. I'm in the process of restoring another one at the minute which will be going to a charity auction next weekend but with that I thought it would be nice to include some sort of modern cartridge solution and so the FE3 seemed a good choice. I decided to get 2 of them, one to keep and one to sell on with the charity auction.

The problem is though that both seem to have issues.

All my machines are PAL. My main machines is a later CR model. All components for both FE3s were new coming from good suppliers (mouser). I have both setup with version 0.29 of the firmware. Can I just check this this the most up to date version?

Trying to run the included FE3DIAG.PRG always yields strange results making me think there is something wrong with the cards. Sometimes the SD2IEC will refuse to read the contents of the SD card (2GB card) but when it does sometimes when I try LOAD"FE3DIAG.PRG",8 the VIC responds with PRESS PLAY ON TAPE as per the below screenshot

Other times when trying to load it will report an illegal device number as per the below

On the very rare occasion that I can successfully load and run the diag software it typically fails either the rom or ram tests as below

As I said I haven't used these machines much but I'm confident my own one which I have been using is in good working order. That said I have tried to run the VIC-20 DIagonstics and it seems to crash straight away just sitting at ZERO PAGE.

I think the first issue I need to tackle is the inconsistency in the SD2IEC side of these. The firmware I have flashed on there is latest from here https://sd2iec.de/ (dated 19-01-23).

Just in case you're wondering I have the VIC attached to a capture card on my PC, that's how I'm getting the screen shots. In terms of the issues though any advice would be greatly appreciated.

[srowe]

All my machines are PAL. My main machines is a later CR model. All components for both FE3s were new coming from good suppliers (mouser). I have both setup with version 0.29 of the firmware. Can I just check this this the most up to date version?

The "official" firmware can be found here, so you're running the most recent version.

I have completely re-written the firmware and added some extra features, but I would advise we identify the cause of your problems before you consider using that.

Trying to run the included FE3DIAG.PRG always yields strange results making me think there is something wrong with the cards. Sometimes the SD2IEC will refuse to read the contents of the SD card (2GB card) but when it does sometimes when I try LOAD"FE3DIAG.PRG",8 the VIC responds with PRESS PLAY ON TAPE as per the below screenshot

This makes be suspect the VIC rather than the FE3 carts. What happens if you try LOAD "SOMETHING",8 without them connected?

As I said I haven't used these machines much but I'm confident my own one which I have been using is in good working order. That said I have tried to run the VIC-20 DIagonstics and it seems to crash straight away just sitting at ZERO PAGE.

That is normal behaviour if you don't have the cable harness connected.

Just in case you're wondering I have the VIC attached to a capture card on my PC, that's how I'm getting the screen shots.

They're really impressive shots.

Simon

[CRG(Glen)]

Well it seems you may well be correct. I pulled out a spare VIC20 board I had popped both FE3s into that and both read from their SD2IEC fine and run the diags fine too, no failures.

So must be a fault on my other board then. Swapped VIAs which was easy since they are in sockets but it made no difference. Could it be UB4?

[srowe]

So must be a fault on my other board then. Swapped VIAs which was easy since they are in sockets but it made no difference. Could it be UB4?

There's several possibilities, my first thing to check would be the KERNAL ROMs. They seem to be able to experience an intermittent failure mode, which makes identifying the cause difficult. Do you have a way of burning ROMs for a cartridge? If so you might find that this dead test image helps prove this one way or another.

[CRG(Glen)]

I can write a rom easily enough but not sure I've got any of the required roms in stock. The kernal roms in both boards are in sockets too so I can easily swap them over to test with.

If I wanted to make dead test cart, are there any PCBs gerbers available anywhere?

[srowe]

I can write a rom easily enough but not sure I've got any of the required roms in stock. The kernal roms in both boards are in sockets too so I can easily swap them over to test with.

What size EPROM do you need, I can drop one in the post.

If I wanted to make dead test cart, are there any PCBs gerbers available anywhere?

I haven't come across any, I built mine by hand from the diagram here.