Luis' Build

[lrodriguezrullan]

Today I assembled my H5 C1 board with some parts removed from my old 1040 STF, other parts purchased from Exxos' store, and a 4MB SIMM I got off eBay. I am testing a minimal configuration and getting a white screen.

I have not installed the floppy power lead, the floppy ribbon cable, the RS232 connector, the printer connector, the external floppy connector, the cartridge port, the DB19 port, or any 68K sockets.

I configured the jumpers based on a post for the H5 A3 as best as I could. I am especially unsure about the blitter jumpers and the TOS select jumpers.

I am using a fairly new PSU from Exxos' store that works fine with my other ST.

Am I missing anything?

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[exxos]

It looks OK at first look. but no ROM shot ? Tried the ROM jumper ? What about the jumpers to the left of the simm ?

[lrodriguezrullan]

Thanks for taking a look.

Please find a picture of the ROM attached. I tried both settings on the ROM jumpers with no success.

I just noticed that I am missing a jumper near the DS1315. Could that be it?

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[lrodriguezrullan]

I added the jumper near the DS1315. Still get a white screen. If I change the TOS jumper, I get a black screen with a white border.

[exxos]

I just noticed that I am missing a jumper near the DS1315. Could that be it?

That won't stop you booting. What about ram jumpers ? Have you checked all your chips work ?

[lrodriguezrullan]

I am currently testing with all the RAM jumpers open. I also tried with all closed. Have not tried other combinations. I will do that now.

I am not sure that the chips are good. They come from an old 1040 STF motherboard that does not work. I could get some from my other working STF, but I'm afraid of ending up with no ST.

When I get the black screen with the white border, the reset button appears to work.

Thanks!

[lrodriguezrullan]

Tested the RAM jumpers in all combinations. No changes.

[exxos]

Tested the RAM jumpers in all combinations. No changes.

They should be all closed.

You should test the chips in a working ST , if they are good, start here https://www.exxosforum.co.uk/forum/viewt ... =78&t=2362 and probably try a diagnostic cartridge.

[lrodriguezrullan]

I will do that. Thanks.

[lrodriguezrullan]

I replaced all the chips, except the Yamaha one, with chips that work on another ST. Same results (white screen). Would a bad Yamaha chip keep the board from booting?

Thanks.