The Sinclair QL Forum

I am doing some code which relies on the system speed. I tried using different emulators to get an idea of the original QL speed. I did 3 screenshots. They show very different performance. It seems MESS/MAME is massively inaccurate. QemuLator and sQLux show close results, so I can think that they are close to real hardware. However I am not sure. I have attached my program here. This program very quickly generates 16 Mandelbrot images. I am looking for results (a screenshot) from the QL with the 68008@7.5 MHz. I don't know are there ways to increase the QL performance besides the CPU upgrade. So I am also curious are there other ways to make the original QL faster? Thank you.

Speed varies mainly with the fact if external extended memory is available or not. The internal memory is contended with the screen refresh and slow in comparison. Different OS can also make a difference, depending on how many facilities are used in the application (maths library or whatnot). In your case OS doesn't make a lot of difference, though QDOS is a bit faster (which is counter-intuitive). But putting a TrumpCard memory expansion in makes a HUGE difference (much more than I would have expected)... it's all the same QL BTW, with a QL-SD ROM drive to switch the OS.

QL 128KB Minerva QL 128KB QDOS QL 768KB TrumpCard QL 4MB SGC

vol wrote:I am doing some code which relies on the system speed.

Why is sQulx so slow is it running at QL simulation speed or are you running it on a 33 MHz 486?
I remember doing a Mandelbrot on a 286 then adding a maths coprocessor where the difference was minutes down to less than a minute and I thought that was ace. That's the days when WIndows was written in Pascal and any upgrades made a difference in speed

Ruptor wrote:That's the days when WIndows was written in Pascal ...

Windows? Pascal? Are you sure, because I was of the understandingthat it was Macintosh no Windows. I've not found anything online about windows, but a few about Mac:

The Classic Mac OS, known at the time as System 1, was written in Motorola 68000 assembly language and Lisa Pascal.

Lisa being the Apple product that bombed, big time. I actually liked it, I was working on a college placement at the North of Scotland Hydro Electric Board's computer centre in Aberdeen and Apple can to us to give a demonstration of the Lisa. It wen't down rather well at the time, but went down too well when it was released.

Cheers,
Norm.

Hi,

Is the source code to the Mandelbrot rountine available?

NormanDunbar wrote:Windows? Pascal? Are you sure, because I was of the understandingthat it was Macintosh no Windows.

Early Windows versions were written in assembler of course, later gradually moving to C and even later to C++. The Win16 API does use the so-called Pascal calling convention, but that was a conscious decision to save a few bytes on every call (C calling convention must clean up the stack on every caller location). Back then the Microsoft developers actually had to fight for every byte, too...

Back to my original question with corrected spelling. .

Ruptor wrote:Why is sQlux so slow is it running at QL simulation speed or are you running it on a 33 MHz 486?

The numbers don't look right to me.

NormanDunbar wrote: Windows? Pascal? Are you sure, because I was of the understandingthat it was Macintosh no Windows.

Up to Windows 3.1 at least parts of WIndows were written in Pascal.
Windows 95 was written in Watcom C. God, it was taking hours to compile anything!

Andrew wrote:

NormanDunbar wrote: Windows? Pascal? Are you sure, because I was of the understandingthat it was Macintosh no Windows.

Up to Windows 3.1 at least parts of WIndows were written in Pascal.
Windows 95 was written in Watcom C. God, it was taking hours to compile anything!

Were you at Microsoft? I was from '05 to '07 but then things were C/C++/C#.

Andrew wrote:Up to Windows 3.1 at least parts of WIndows were written in Pascal.

I could find not a single source for that.

Windows 95 was written in Watcom C. God, it was taking hours to compile anything!

At that point they had their own C compiler for 10+ years, why would they use the competition?