Atari lost all power after installing 6 TOS 1.04 ROM chips.

[Cosmic Puppet]

I tried a new fuse thinking something had blown. Still no power. Installed 6 chip set as shown in instructional picture. I took them out and put back the original chips and everything works perfectly. Maybe my board is missing something? I'm out of my depth. Fixed a broken IDC connector on the floppy drive. Installed the Marpet, but this is now beyond my understanding. I really thought I'd broken my brand new Atari. :shock:

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[Icky]

Hi. Sounds like you have quite a few upgrades going on at the same time. TOS and Marpet installs.

With the original chip back in place is the Market working? Just to rule that upgrade out.

[Cosmic Puppet]

Hi. Yes, the Marpet was working and Notator now successfully loads following that upgrade (which was completed before the ROMS were ordered. I was struggling to navigate the site so didn't do a proper introduction. I had used an Atari ST for14 years and even written an album using it before it because so unstable as to crash upon loading in 2009. Turns out it had more done to it than I realised. A Marpet had been installed by the music shop technician and had involved a lot of soldering due to the chip being unsocketed. I have had to do the same upgrade on the new Atari in order to run Notator. (Luckily this one was socketed and just required the 2 jumpers to bypass the original 520 memory.

Basically I've never found a MIDI sequencer I could write so easily with and wanted to get that back.

[exxos]

Can you post a image of your board with the new ROMs placed on top of the old ROMs so we can see how you fitted them ?

If the ST lost power as in green light no longer came on, then sounds like you may have fitted the ROMs backwards shorting out the PSU.

[Cosmic Puppet]

I tried it these 2 ways.

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[exxos]

If you had them in like that then they are upside down... So they would short out the PSU and likely have killed the chips as well :(

[Cosmic Puppet]

:( I'm flat broke for a month now. Could you post a pic of the correct configuration please?

[frank.lukas]

The print on the PCB are sometimes wrong !

[exxos]

Images are here http://www.exxosforum.co.uk/atari/last/t ... m#TOS6CHIP

You actually have the order wrong as well...

You could still try the chips in the correct locations, you may get lucky.. No harm in trying .

[Cosmic Puppet]

I did try the right order the second time but it seems they were upside down. Should that little notch on the chip be facing upwards? I assumed the writing was to go the same way as the writing on my original chips.