The Sinclair QL Forum

What is the QL emulator with the best debugger? Something that allows to step into assembly, look at the memory.

I tried to look at MAME but I cannot find the appropriate ROM (the link from that forum expired).

ecdhe wrote: Tue Jun 24, 2025 3:46 pm What is the QL emulator with the best debugger? Something that allows to step into assembly, look at the memory.

Qemulator has a good host-based debugger (it runs outside the emulated QL).

Hi,

you could use QMON, Computer 1 Monitor, Multimon by Jan. Available on QL Homepage.

Which run on all QL systems, emulator or hardware.

I prefer MultiMon

Thank you for the suggestions, I took a look at them. Because I'm trying to understand how existing games work, I'm not sure if a debugger running inside the emulator would work well.

Q-Emulator does have a debugger, however limited. For example, there doesn't seem to be a way to add a watchpoint or dump the whole memory to a file.
MAME has a proper debugger, however I was not able to read any file from the emulator.

Hi,

Have tried zesarux:

https://github.com/chernandezba/zesarux

which also has emulation debugger.

Derek_Stewart wrote: Fri Jun 27, 2025 10:23 pm Hi,

Have tried zesarux:

https://github.com/chernandezba/zesarux

which also has emulation debugger.

I did try this one, and it does seem to have some of the debugging features I'm looking for. However I was not able to get it to recognize .mdv files.

By debugging Q-Emulator using Windows kernel debugger (windbg) I was able to dump a memory snapshot of the QL onto disk. Not the most straightforward process by any mean but at least it does the job. Which allowed me to understand how the animation of MatchPoint is made.

I am still interested if there are easier ways to dump the memory of a QL program in .mdv form.

The code to add a memory dump in sqlay3 would be really simple. I could do that if it would help you. It would be a raw binary of memory space.

I assume you're talking about https://github.com/xXorAa/sQ68Lay ?

For this emulator I wasn't able to get anywhere as I wasn't even able to insert any microdrive file (the -l option doesn't seem to accept .mdv files). Is there a documentation somewhere?

:~/sQ68Lay$ ./build/sqlay3 -f sqlay3.ini

sqlay3.ini
sysrom = /home/two/sQ68Lay/roms/min1.98a1.bin
#exprom = /home/two/sQ68Lay/roms/NFA.rom
drive = mdv1@/home/two/sQ68Lay/MD2BOOT.mdv
ramsize = 640

hope it helps
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