The Sinclair QL Forum

... On a newly designed system, you probably want to start from ROM and run there, without runtime relocation. Tobias Unless of course your RAM is 32 bits wide and your ROM is 8 or 16 bits - then you want to be running code out of the RAM, and suffer the relatively small copy overhead. Wastes eithe...

If I've understood SMSQ/E correctly - it allows for some holes in the memory below the screen area, to accommodate the gold / super gold cards? Areas such as the 16K ROM slot space at 0c000 and the QL I/O area... SMSQ/E for the GC/SGC is a bit different in that it run-time relocates its modules whe...

Well, the vector area needs to start at address 0, to tell the CPU where to start. In case you don't want to place the whole OS starting from there, you have to implement some shadow RAM "behind" the ROM there, and at least put some minimum code that sets the Vector base register to the pl...

What did the Q40 and Q60 boards do? As they could not run QDOS given the processor differences? Was there a BIOS of sorts to handle the ability to boot SMSQ from a floppy or hard disk? As long as SMSQ/E fitted into their ROM space, they booted SMSQ/E from there. Once the OS outgrew the ROM space, y...

Dave, There absolutely is nothing in SMSQ/E to prevent it being put into a ROM. The Q40 and Q60 used to have SMSQ/E in ROM as long as it fitted into their standard 256kB (Today it doesn't any more). In case you provide 512k of ROM space, you can easily fit SMSQ/E in there. (http://qlforum.co.uk/view...

Note a lot of the earlier boards have been factory upgraded when sent in for repairs. So all sorts of mods might have been done depending on when exactly the repair was needed.

Tobias

Actually, none of your arguments really speaks against an FPGA. The best one possibly is that you stick with what you know and most feel at home with when having the choice between a µC and programmable logic - I would do the same (but maybe wouldn't use a Propeller, as I don't have a single clue on...

Well, no wonder:

Both the Spectrum with I/F1 and the QL bit-bang the protocol at 87500 bps - Not an easy task for a poor Z80. It's probably at its limits.

Nice to hear you're making progress.

Tobias

Nah. The main limitation is it's not implemented for anything but microdrives ;) Such a function would maybe also not bring a lot of benefit for disks - Microdrives can profit a lot from scatter/gather-reading all sectors in one go and then re-organizing into files on a ramdisk. This can copy all of...

Dave,

there's no such thing as support for "format ram1_flp1_" or the like - For a DD disk, you'd need 720k capacity on the ramdisk, which is practically imposseble. This command works with microdrives only.

Tobias