How to slow down the bus speed ?

[AndyS]

I have a Modular Circuit Technology EPROM programmer that
I bought 15 years ago, and used with a PC-XT 4.77 Mhz and
it worked well.

However, I no longer have the old XT and would like to use the
programmer with a later model computer.

The problem is that the programmer cannot be used with a
system that has a bus speed of above 8 Mhz...

So, does anyone here know whether or not there is a software
program that will slow down a computer's bus speed, maybe by
using wait states or something, that will enable me to use
the programmer with a more modern computer ?

Perhaps, if this isn't the right group to ask, someone could
tell me about a computer newsgroup where I could ask.

Thanks for any advice you may have.

Andy W4OAH

 

[[email protected]]

I have a Modular Circuit Technology EPROM programmer that
I bought 15 years ago, and used with a PC-XT 4.77 Mhz and
it worked well.

However, I no longer have the old XT and would like to use the
programmer with a later model computer.

The problem is that the programmer cannot be used with a
system that has a bus speed of above 8 Mhz...

So, does anyone here know whether or not there is a software
program that will slow down a computer's bus speed, maybe by
using wait states or something, that will enable me to use
the programmer with a more modern computer ?

Perhaps, if this isn't the right group to ask, someone could
tell me about a computer newsgroup where I could ask.

Thanks for any advice you may have.

Andy W4OAH

People laugh at me when I dumpster dive or pick old PC's
out of the trash and take them to my warehouse. I still have
customers who are running DOS. The proprietary software
they have won't run on modern systems. I have seen some
software for the avid overclocker crowd that allows all sorts
of adjustments to motherboard buss speeds that could be
useful to you but I have not used any of it. You may have
to bite the bullet and cruse the thrift stores and recyclers
to find suitable hardware.

"Command line", never forget.

[8~{} Uncle Monster

 

[Jamie]

I have a Modular Circuit Technology EPROM programmer that
I bought 15 years ago, and used with a PC-XT 4.77 Mhz and
it worked well.

However, I no longer have the old XT and would like to use the
programmer with a later model computer.

The problem is that the programmer cannot be used with a
system that has a bus speed of above 8 Mhz...

So, does anyone here know whether or not there is a software
program that will slow down a computer's bus speed, maybe by
using wait states or something, that will enable me to use
the programmer with a more modern computer ?

Perhaps, if this isn't the right group to ask, someone could
tell me about a computer newsgroup where I could ask.

Thanks for any advice you may have.

Andy W4OAH

Hmm, is it possible that the software you're using has the
problem and not the hardware?
I do remember back in the Turbo Pascal days of using the
Delay function. It used CPU counting, that program would fail
on faster machines because it would over flow .

You could call it built in obsolescents.
The fix was, I wrote my own CRT unit and used the tick timer
window....
If you know the programming sequence to the programmer, I'm sure
it would be simple to whack out a program to dump a bin file to the
programmer.
I suspect that the software you're using must be using a delay loop
when communicating with the COM/Parallel port. Because that was a common
thing back then.

 

[AndyS]

Jamie wrote:> I suspect that the software you're using must be
using a delay loop

when communicating with the COM/Parallel port. Because that was a common
thing back then.

Andy writes:
It says SPECIFICALLY in the manual that it cannot be used with
bus speed of greater than 8 Mhz.

While I know it is possible to trace out the circuit and write a
program that
will run thru a printer port to simulate a low speed computer, I have
retired and
am too damn lazy to start a project like that from scratch..

I just want to see if there is a way to load a "MODERN" program
with a
patch that will automatically provide a couple of hundred wait states
after each
instruction and allow the effective bus speed to be below 8 Mhz.....

Yeah, I know,..... but I am too damn old to be smelting my own ore
to
get the metal to build a screwdriver......

Thanks , tho, for your post...... My background is both hardware
and software,
but I don't have the enthusiasm to pursue the building of new tools
anymore...
Hell, I'd probly just use flint arrowheads if I could get away with
it...
.... which is why I don't just pay $500 for a new programmer that will
replace the
one I have.... :>)))

Andy

 

[joseph2k]

I have a Modular Circuit Technology EPROM programmer that
I bought 15 years ago, and used with a PC-XT 4.77 Mhz and
it worked well.

However, I no longer have the old XT and would like to use the
programmer with a later model computer.

The problem is that the programmer cannot be used with a
system that has a bus speed of above 8 Mhz...

So, does anyone here know whether or not there is a software
program that will slow down a computer's bus speed, maybe by
using wait states or something, that will enable me to use
the programmer with a more modern computer ?

Perhaps, if this isn't the right group to ask, someone could
tell me about a computer newsgroup where I could ask.

Thanks for any advice you may have.

Andy W4OAH

I have an old ISA bus device programmer as well. I haven't had an ISA slot
to plug it into for some time now. My new programmer is USB2, it cost me
about U$200. Decide whether to support antiques, or support newer stuff.

 

[JeffM]

It says SPECIFICALLY in the manual
that it cannot be used with bus speed of greater than 8 Mhz.
. . .
I just want[...]a patch that will automatically provide
a couple of hundred wait states after each instruction
and allow the effective bus speed to be below 8 Mhz.....

Wait states are set in CMOS Setup.
AFAIK the most ever available is 3.

Here's what AMD has to say:
http://www.google.com/search?q=cach...the.older.CPUs+updated.version&strip=1#102553