The Sinclair QL Forum

Can the ROM code be put anywhere in memory? My ROMs have addresses of 0000 and 8000 written on them implying the code is not relocatable but could it be made relocatable?

Depends on why you ask. The code itself is probably pretty position independent, but some stuff like QL vectors have to be at certain positions by definition.

+1 on that - the QL used fixed addresses for the vectors it works with - although a group of the standard 68K vectors are relocatable on a per job basis.

You may want to visit Dilwyns excellent site: http://www.dilwyn.me.uk/ and dowloand the QL tecnical guide - it's a heavy read - but contains all sorts of infromation about QDOS and it's various components and has details of the memory map.

mk79 wrote:Depends on why you ask. The code itself is probably pretty position independent, but some stuff like QL vectors have to be at certain positions by definition.

I have some components lying around like a 68010 on a board with a couple of MMUs and other stuff so thinking about putting them all together with QDOS. Of course biggest problem is the video memory and output. I am just considering what is involved with modern components making things much easier like one chip for 500K memory.

Fun project but sounds like position of the OS is the least of your problems then Video is one problem, but there is also keyboard access and stuff... of course there is the QDOS classic source code that could be changed for different I/O hardware if not aiming at register compatibility.

mk79 wrote: Video is one problem, but there is also keyboard access and stuff... of course there is the QDOS classic source code that could be changed for different I/O hardware if not aiming at register compatibility.

Yes since the source is available I was thinking of hacking, I mean adapting it for a serial keyboard and a small boot loader to dump the OS in Ram at power on from a USB stick. It could run any operating system that way in theory. I suppose the video output from QDOS could be changed to anything like writing to a completely separate memory out of the main map so main memory would be contiguous especially since the 64 pin chip has more memory lines. Wait a minute this is turning in to an issue 8 QL in terms of elapsed time. I think I will try fixing my original QL first.