Right, forgot for a moment that this is not tektronix executable code and it couldn't care less about checksums.
Many years ago, I worked on a mil-spec processor system that had a lot of that in the startup code.? Considering it was made of discrete chips, it made sense.
Harvey
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On 4/13/2024 1:04 AM, Chuck Harris wrote:
Hi Harvey,
The checksums are read by the normal tektronix EPROM code.
We are making the rules here, not tektronix ;-)
Well, tektronix made the sand box we are playing in, but we
will be running only our code, and our code doesn't calculate
checksums.
-Chuck Harris
On Sat, 13 Apr 2024 00:32:36 -0400 "Harvey White"
<madyn@...> wrote:
Looking at some Tektronix code, it occurs to me that some of that
data in the EPROM is a checksum, and changing data without changing
the checksum will be a problem.
That's what the disassembly is going to be for, amongst other things.
Not sure where they did it, but this code dates from the paranoid era
of microprocessors where you have jump tests, load and store tests,
subroutine tests, etc built into the startup code.? I know that on
the DC5010 there's a bit of it.
So changing things may be a bit more complex than let on (if they did
that on the cal data).
Harvey
On 4/13/2024 12:24 AM, Chuck Harris wrote:
Hi John,
Any hex editor will do. Most eprom programmers come
with one in some form.
-Chuck Harris
On Fri, 12 Apr 2024 18:33:44 -0600 "John Griessen via groups.io"
<john@...> wrote:
On 4/12/24 17:52, Chris Elmquist wrote:
Other folks will put their own
constants into the same place in the program, keeping only the
copy routine ahead of them but we can then show the constants in
spreadsheet form and also in hex form in the program so folks can
see where they go.
What tools will we need to edit the EPROM data on linux? Vim? An
assembler? Straight machine language only with vim, nano, gedit,
etc.? Maybe more than a couple will use linux to do this...
