Microwriter hard reset?

[Tony Duell]

Does anyone have a user manual for a Microwriter MW4 chording keyboard-thing?
 
If so, is there a procedure given to do a hard reset if the batteries 
have gone totally flat and you've recharged them? I have one of these 
devices which I am currently running off my bench supply (4.8V) in place 
of the NiCd. It seems to power up OK, and you can type exactly 8 
characters befroe it locks up. 
 
Before I start testing the processor (1802), RAM (6116s), etc, I wondered 
if it was simply not initialised correctly and I needed to do some kind 
of hard reset.
 
-tony