Hello Celso,
I understand what you mean. Its really old stuff I am looking for. I
already know that those devices could be monitored somehow.
The "normal" G" ( 705G2S ) can be read easily and also programmed.
Reading is done by verification of the contents ( detect A0 and CE, force
reset, present data, as an endless loop, and takes long. I have programmed
such a G2S with an external EPROM and I could get out the contents
within one week - dont laugh, it really took so long.). The EPROM file
was identical to the verified dump.
The problem is, that the G2L1 type cant go into verifying mode by grounding
VPP and switching -12V to IRQ, like the G2S.
The G2L1 is similiar to some SC and ZC commercial types, which also
cant be read out. They also dont want to go into verify mode. The software
works correct....
Michael