Acorn A5000

Acorn A5000

Very dirty. And Rusty.

After cleaning with acetic acid & IPA

Disk drive flashes with a fault code: 00010059  Simulate &00010059

• CMOS unreadable
• PC-style IO world detected
• ARM 3 fitted/ARM ID read and not ARM2
• Long memory test performed
• Self-test due to power-on
• 
  
• So some work needed around the CMOS.

UPDATE: 2018-09-23

Fixed the corroded CMOS tracks

It Lives!

Sorted the rust & painted (Needs lettering)

Almost the right grey, but shows up the disk drive :-o

RiscPC 700

Poor old RiscPC suffered the common battery leak from the PCB mounted NiCd.

Sadly it caused some damage to tracks around the CMOS clock and memory.

The charging circuit for the NiCd was also damaged.

Things I know that work now:

* Charging - Replaced the failed 180R resistor with a through-hole type as I needed to also get power from the diode and the track had disintegrated. Not pretty.
* CMOS I2C - I watched the waveforms on the logic analyser.
* Sound & Video from VIDC

Battery replacement. NiMh hidden well away from the PCB

 Life! for the first time since 2009!

Little bit better!

Some more cleaning of SIMs & VRAM

Passable, but I think the VRAM needs replacing now.

Well, that's the most life I've had out of this recently, so I'm a bit happier with it. Still some way to go.

Next steps.  Some new RAM and VRAM.