[chbot] 6809 Processors

[Volker Kuhlmann]

On Mon 03 Feb 2014 08:40:14 NZDT +1300, Marshland Engineering wrote:

> It's old but very useful and accurate. It uses a 2 x 6809 processors
>to do the work.

Charles' suggestions are no doubt good. What makes me suspicious is the
gradual worsening of performance of the digital parts. ICs so wear out
at some stage, because atoms in the fine structures start movoing
around. Operation at the limits of current and voltage doesn't help.

Whatever the problem, you do need good transient suppression, a clean
power supply for the digital side, and a good ground between the digital
circuitry and the power drivers. Separate the return paths for the high
current circuits from those for the controller and power drivers.

If the problem is degrading ICs perhaps this can be shown by swapping
the two 6809 - but double check they are identical. If that's the
problem you'll have to find replacements. Is there an Arduino 6809
emulator...? There are trade places for historic microchips (not cheap).

Volker

-- 
Volker Kuhlmann
http://volker.top.geek.nz/	Please do not CC list postings to me.