In the first post of this series I removed the leaky battery and cleaned up underneath. Now it is time to see if this machine boots and if there are any hardware issues before going further.
First Boot Woes
I acquired a SCART cable for the machine, hooked it up to my screen and attempted to power it from my bench power supply. Holding down the “Del” key to clear the NVRAM settings when powering on, I was faced with a white screen, which is a little odd.
It is difficult to diagnose past this point with the built-in RISC OS 2 ROMs, but as it happens I have also acquired some RISC OS 3.11 ROMs for this machine in anticipation of upgrading at a later date. This is significant here because RISC OS 3 shows a diagnostic flashing sequence on the floppy drive when there is a boot problem.
Note that the jumpers needed changing for the new ROM size. There is a diagram on how to do this as part of an upgrade manual. Normally LK17 and LK18 would be vertical and LK19 / LK20 would be set to 2-3 for RISC OS 2.0.
Video Issue?
I attempted to boot again, holding down “Del” to reset, and again a white screen. I’d expect either a logo screen, or red screen whilst the NVRAM is reset. But also it made the familiar Acorn boot beep. So, maybe there is something up with the video? Luckily the A3000 has a composite output as well, very much like the Amiga 500. So, I hooked this up to my screen.
Oh! It is working… Then why isn’t the RGB port? Maybe, just maybe, my screen doesn’t like the input. I decided to try hooking the SCART cable up to my OSSC and plug the HDMI output of that into the screen. In theory I should be able to tweak that or use it to diagnose the image.
It worked immediately! At least I know that the output image is incompatible with my screen now. Also, the machine boots!
Unfortunately I’ve somehow misplaced my A3010 mouse and the PS/2 to Archimedes mouse converter I have doesn’t fit in the small space under the computer, so I can’t get much further with the OS. I have a solution for this coming which I will talk about soon.
Next Steps
I need to pull this motherboard out and replace all the pin headers that have corroded, build the battery solution for it and then work on the power supply. Until then I’m super happy that the machine gets this far with very little effort!
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