Re: IEEE 488 used to connect at PC directly to SFD 1001

From: Claus Just Rasmussen (
Date: 2006-02-28 23:17:02

Hi Ruud, wrote:
> Hallo Claus,
>> [ Note: This mail was converted from HTML to text by majordomo.
>>         Formatting might be poor. ]
> Which makes it a bit hard to read when used to using '>' etc.
I noticed, and I'll try to remember to use txt! :-)
>>   OK. And the diodes etc to be added to the cable ?!
> I was a bit wrong with the number of diodes etc. please see:
> My own solution was soldering a 25-pins female and male D-connector to 
> eachother and place that between the origanal cable and the LPT-port. The 
> transistors, diodes etc. were soldered on a piece of experimental print 
> which was connected with two cables to this D-connector combination and a 9-
> pin D-connector for the RS232 port 
OK. Tnx for the diagram. That's not too bad. And a nice idea to add this 
female/male connector to a cable instead of modding an existing cable!
>>   BTW: My impression is that the 'Commodore-related' PC software are
>>   all running under DOS, sometimes W95 but never WinXP. Except for the
>>   Vice emulators. Is that true?
> This is because of the tricky timing needed for some operations. In some 
> cases you only have a window of less then 70 micro-seconds to react. With 
> DOS you can time things quite good, but with Windows it can be horrible 
> because of a bossy OS that sticks his nose in everything you do. 
Yes. True. 70us, that's snappy =:-O

It would actually be interesting to use some new cpu-ram-flash 
single-chip combination as middle-man and program it to do the 
timing-critical parts. But... I must admit that I would also prefer a sw 
solution, it's easier after all. Don't know XP well enough - it might be 
possible to do a low-lever driver with ok timing? Or maybe Linux instead?

How about running W98 as a virtual PC under Linux or WinXP. Would that 
work? (actually expect not, since at least XP would still prevent direct 
HW access, or?!)
> Vice is a different thing because with emulation there is no external 
> device putting a pressure on you. OK, I know that the new version can 
> handle external drives as well buy IMHO it was only possible by using the 
> massive power of nowadays processors. I wonder if it could be done with, 
> let's say, a 100 MHz Pentium-1.
> Spiro, maybe could you explain this a bit more, please? Thanks.
Yes, no doubt that modern processors helps a lot. I also find it amazing 
that we can run stuff like Vice and run these old computers (virtually). 
Of course - computers at that time were slow, but we still has to 
emulate the HW too. Really nice !!
> A personal note: there are a lot of discussions going on about "why doesn't 
> Star Commander run under XP?" and "how can we can we make it work under 
> XP". It works perfectly under DOS. So I have a 486-80 MHz doing this for me 
> running under W98-DOS. And if I need to exchange files, I start up the GUI 
> to be able to use my network. Really no Windows version of SC needed, I 
> think.
I can easily follow you here. For my part, I dropped older than WinXP 
due to stability. But W98 is far better when it comes to playing with 
hw-near stuff. So...

> --
>     ___
>    / __|__
>   / /  |_/     Groetjes, Ruud
>   \ \__|_\
>    \___|
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Claus Just Rasmussen

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