The Sinclair QL Forum

Mark Swift wrote: ↑Thu Dec 22, 2022 3:39 pm Both QDOS4Amiga and its successor QDOS classic are not really emulators. They are a port of the JS ROM to the Amiga. So QL code runs as-is without modification which is why your 68K 7.16 MHz machine runs at full speed.

And not just that - it is basically a portable version of QDOS that is capable to run on different kinds of 68K hardware.
Not only that Mark ported it to the Q40 and Q60. Even with my very limited assembler skills, I was able to port it to the Q68 in just one day.

I'm delighted to see you appear on this forum Mark! Hope you are fine!

Merry christmas to all
Peter

I like playing with emulators. I've seen plenty of evidence that an Amiga can run a Mac really well...maybe even faster at times than the real thing. I think they use the same technique that Mark sued for the Amiga's QL emulator, having the 68K mc code being directly executed by the processor.

Today I decided to go the other route and have my 68K PowerBook 180 (33Mhz 030) run an Amiga emulator (UAE 0.6.0 for the Mac). That was painful as UAE for 68K actually emulates the processor and it was unusably slow. Very stable and executed everything I tried...even had sound...but impossibly slow to use. I think they never got rid of the double emulation because power PC was taking off at that time for Apple, so probably saw no need to remove the actual 68K emulation since the faster Mac's needed it.

Hello. Looks like this Mac is about the same generation as the Amiga itself.
I suppose emulation only comes into its own when the emulating hardware is of a better spec than the emulated hardware.

I notice that you created a speed test thread a few years ago
viewtopic.php?t=3213
It would be interesting to know how much slower than a real QL this setup is.

Mark Swift wrote: ↑Sun Feb 26, 2023 11:39 am Hello. Looks like this Mac is about the same generation as the Amiga itself.
I suppose emulation only comes into its own when the emulating hardware is of a better spec than the emulated hardware.

I would have thought a 33Mhz 68030 would have done a bit better job emulating a 7Mhz 68000. Not saying it should be as fast as an actual Amiga 500, but would have been nice to see how fast it could have run had they optimized it somewhat (i.e. utilize the 68030 directly like you did with the Amiga's QL emulator)

Interesting, I accidentally stuck your QL Kickstart.rom in there by accident, and up popped the QL

Mark Swift wrote: ↑Sun Feb 26, 2023 11:39 am I notice that you created a speed test thread a few years ago
viewtopic.php?t=3213
It would be interesting to know how much slower than a real QL this setup is.

I've actually been playing around with the Dhrystone code on my QL. I should give that a try. Unfortunately the compiler I'm using isn't very good so I'm not even getting close to the speeds of the other compilers...and I'm trying to avoid cheating.

bwinkel67 wrote: ↑Sun Feb 26, 2023 9:01 pm I've actually been playing around with the Dhrystone code on my QL. I should give that a try. Unfortunately the compiler I'm using isn't very good so I'm not even getting close to the speeds of the other compilers...and I'm trying to avoid cheating.

Why not use the already established Dhrystone executable? http://qdos.free.fr/files/dhrystone21.zip

bwinkel67 wrote: ↑Sat Feb 25, 2023 12:06 pmI've seen plenty of evidence that an Amiga can run a Mac really well...maybe even faster at times than the real thing.

You don't need to go to Amiga for that, the QL had Q40/Q60. MacOS on the Q60 runs extremly fast, much faster than any Apple hardware ever did (using Basilisk).

Peter wrote: ↑Tue Feb 28, 2023 12:29 pm You don't need to go to Amiga for that, the QL had Q40/Q60. MacOS on the Q60 runs extremly fast, much faster than any Apple hardware ever did (using Basilisk).

Which version of Q60 Linux were you using, Shoestring Linux was a little slow on a Q60-66 but had more functionality than the previous version Q60 Linux. But I managed to compile UQLX and run it fairly well.

The execution speed of Basilisk did not depend on the Linux version. Note that UQLX emulated the 68K CPU, while the Q40/Q60 version of Basilisk did not. Hence the speed.

Peter wrote: ↑Tue Feb 28, 2023 7:16 pm The execution speed of Basilisk did not depend on the Linux version. Note that UQLX emulated the 68K CPU, while the Q40/Q60 version of Basilisk did not. Hence the speed.

Did you port Basillisk tomtge Q40/Q60?

Peter wrote: ↑Tue Feb 28, 2023 12:23 pm Why not use the already established Dhrystone executable? http://qdos.free.fr/files/dhrystone21.zip

I wanted to improve upon it.