Sigh. Bringing up a PDP-8/M

From: Allison J Parent <allisonp_at_world.std.com>
Date: Wed Apr 14 21:45:46 1999

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<Indeed you have... In fact, IMHO, everyone here who does design, or
<serious logic troubleshooting/repair should consider this instrument. Yes
<it's expensive (\pounds 550+tax in the UK). But I think it's well worth it

Well I don't have to have it... I have a 16 channel analyser good to 20mhz
and two 0'scopes and a custom anlyser hack I did years ago. Generally if
I have to bring out the scope it's nasty. The 8f was trouble shot with
nothing more than my fluke 12 multimeter as it ws closest at hand.

<Even an LED and a resistor (between an IC pin and ground) is a good
<start. No you won't see fast pulses. But you will see things that are
<stuck it totally the wrong state. I debugged my first homebrew
<microcomputer (SC/MP + RAM, basically) using just such an LED+resistor

I have one in a clear pen barrel with a point and and a cliplead, very
handy! It's pretty easy to tell, high low and something that's pulsing
even at high rates. Another handy item is a 4040 cmos counter to make
fast things into tones (earphone). That trick came from the NS* disck
controller troubleshooting hints.

Intelligently used simple tools can be very useful.

Allison
Received on Wed Apr 14 1999 - 21:45:46 BST