[time-nuts] RS232 488 GPIB controller update Sucess

paul swed paulswedb at gmail.com
Sat Nov 19 21:43:29 EST 2011

Hello to the group.

I sent a thread a few days ago about the traditional IOtech, Black box, and
NI stand alone rs 232-GPIB 488 converters.
Here is the whole story. They can all made to be full controllers. Very
simply by changing a 27c64 eprom.

There was some confusion.
The Iotech 488/ex is a full controller with clock and calendar. Clever unit.
But most of the boxes you will find at flea markets are what are called
peripheral controllers. They are semi-dumb and can address a single piece
of test equipment.

However as it turns out these units can not use the 488ex eprom because
they have no clock calendar ds1216. I tried, it failed.
If you really want to use the 488ex buy the ds1216 from mouser and also a
cmos lower power ram. But the downside is its $$$ and muss and fuss for not
a lot of value.

But if you put the iotech 488a eprom into the boxes they all become full
bus controllers following the 488a specs and a big plus 57,600 Kb/s serial

I have copied all of the eproms so that I can upload them to Diddiers site
for safer keeping in the next 2-3days. Also will document the switch
settings for my config and how to change the eprom etc.
I am controlling a HP436 power meter right now with a simple basic program.
The benefits of a full GPIB488 controller is that the commands are dumb

Send the unit to remote "remote 13"
Read the meter     "enter 13"
local      "local"

Next stop the HP 5370b freq counter the real reason for messing around in
the first place and the reason this is in Time-nuts.

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