Forgottenmyname - Progress

[PhilC]

Cool, thanks very much for your help and for sending the diag rom.

This fault finding is becoming addictive.

Btw, if you think it's the Ram, then any suggestions where I can start looking before the Rom arrives?

[exxos]

This fault finding is becoming addictive.

You develop twitches and start sleeping less after a while though

Btw, if you think it's the Ram, then any suggestions where I can start looking before the Rom arrives?

Only thing is to check everything on the schematics ... I've been checking everything past 2 days, cant see anything wrong though.

2 machines with the same fault is unlikely to be a fault with soldering or something.

I'm assuming the lower CPU variables are not being set, interput vetors are in lower ram, so if they are not setup, then it would cause such a fault. Though I don't know how far down the ROM code that has to go...

Diagrom will state if its found any RAM or not , and allow testing... Again, the atari cart is useless for debugging because its gets hung up on stuff and doesn't let you run RAM test

I do have YAART cartridge version ....

YAART.zip

(6.29 KiB) Downloaded 138 times

Obviously its getting pretty far in booting to run the cart in the first place.. so maybe YAART will boot... Maybe report amount of RAM and test it... Worth a try if you can do new cart ROMs...

[PhilC]

Yeah I can do new roms, will see if I can burn that tomorrow. Will it boot on my STe as the Mega has been raped and pillaged till I can get some new chips.

[exxos]

Yeah I can do new roms, will see if I can burn that tomorrow. Will it boot on my STe as the Mega has been raped and pillaged till I can get some new chips.

I assume it will work on the STE yes.. pretty sure it does...


Also check the vias , some are really close near the RAM header pins...

1.jpg (47.09 KiB) Viewed 3395 times

2.jpg (23.24 KiB) Viewed 3395 times

Might be worth checking that all the MMU RAM lines are switching, RAS, CAS, MAD lines etc.

[PhilC]

Ok, I can do all that, will let you know how I get on tomorrow.

Many thanks again.

[exxos]

Awesome. I've Uploaded the layer views, so easier to look around for potential via to pad shorts...

https://www.exxosforum.co.uk/forum/viewt ... =19&t=1215

[Icky]

Would be interesting to see a photo of your board with the different memory option being used.

Icky

[exxos]

Would be interesting to see a photo of your board with the different memory option being used.

Icky

https://www.exxosforum.co.uk/forum/viewt ... =50#p10349

[Icky]

Would be interesting to see a photo of your board with the different memory option being used.

Icky

https://www.exxosforum.co.uk/forum/viewt ... =50#p10349

Ah must of missed that one with all the traffic on these threads - Nice pic.

This fault finding is becoming addictive.

You develop twitches and start sleeping less after a while though

I agree this is becoming addictive. Great fun.

[PhilC]

And here it is with the marpet fitted.

Will probably use this for now as I'm loathed to disturb it now it's workingish

20180922_095900.jpg (3.61 MiB) Viewed 3350 times