Hi there, On Sat, 5 Feb 2022, Frantisek Rysanek wrote:
Note that PCI boards do not use "well known" port addresses. ... ... e.g. some interesting work by Michael Chourdakis: https://www.codeproject.com/Articles/894522/The-Low-Level-M3ss-DOS-Multicore-Mode-Interface
Thank you very much for a most interesting and illuminating post, I'll certainly be following up your pointers.
In case you were wondering about running DOS and DOS apps on modern PC hardware, one of the problems you'd face might be that the CPU's are too fast for some old software. Unfortunately the Pascal CRT library (error 200 / division by 0), which is patchable, is not the only such problem. There are other pieces of software affected ...
To the very best of my knowledge I've never had the problem that a CPU has been too fast to do something for me! The code I've written makes absolutley zero assumptions about execution time save that it might be a while before we get a response to something so we should probably do something else in the meantime. For DOS systems, the display code and low-level interrupt routines are written in C plus a bit of assembler. For Linux the display is via the ncurses library and the system itself handles all the interrupts of course. No need for me to get involved, just read and write the pseudofiles. The last time I seriously used a Pascal compiler (well, tried to) was in the late 1970s, when I was the Technical Director of a firm making instruments for nuclear medicine. The compiler turned out to be riddled with faults. Last I heard of it was at Chicago O'Hare airport when I gave an inch-thick printout binder detailing dozens of faults to the supplier's representative. He took it away, and as far as I can remember we never heard from them again. We replaced Pascal with RTL/2 from a company in Oxfordshire, England, which offered remote debugging via our instruments' serial ports... Forgive me if you're fond of Pascal, I did rather like the look of it at the time but back then the implementations seemed a bit patchy. My display frivolities are limited to drawing boxes using the special box-drawing characters (approximately a dozen of them) for DOS systems and direct cursor positioning is about the limit of this folly. Linux builds use the four ASCII characters '=|-_' instead of the box drawing characters. It makes the screens a little less aesthetically pleasing but they otherwise do exactly the same things. People get used to it.
I'm writing all this to introduce my recent "discoveries" allowing me to underclock modern CPU's, using EIST and CLOCKMOD combined, down to a fraction of their nominal frequency... Tried on a Core2Duo and on a Haswell, in DOS. I haven't written a public blogpost on the topic yet... let me know of you need this.
Thanks very much for the offer, but I can't see that I'd ever want any CPU I'm using to go slower. In fact quite the reverse! -- 73, Ged. _______________________________________________ Freedos-user mailing list Freedos-user@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/freedos-user
