6500/1 test mode questions

From: Marko Mäkelä (msmakela_at_cc.hut.fi)
Date: 2001-12-21 12:22:20

MagerValp, could you add Konrad's posting address to the exception table?

If the test mode is anything like the parallel programming mode of Atmel
AVR microcontrollers (which are about 20 years newer technology), then
you'd keep the reset line at 10 volts during the whole process.  But this
is just a guess.  Anyway, assuming that it is a mask-programmed ROM, and
that the pin handles 10 volts, there shouldn't be any risk of damaging the

---------- Forwarded message ----------
From: Konrad Burylo <K.Burylo@elka.pw.edu.pl>
Subject: 6500/1 test mode questions

Hi !

I'm going  to dump 6500/1's ROM  (from 1520 plotter). I've read the 
datasheet and now I know how to switch 6500/1 into the test mode.
I assume I have to provide 64 bytes, that will be written into an internal 
RAM. But there is no info on how memory fetches from port C are 
synchronized. And for how long should I keep 10 V at Reset line ?
Any ideas ? Someone knows something about 6500/1 test mode ?

I think that for the beginning I should use an oscilloscope and check all 
the pins - to see if any of them is used as read strobe. But any info will 
be appreciated...

Konrad Burylo

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