The Sinclair QL Forum

Now this is a challenge (you may want to get hold of the DEAssembler from Ergon for this) - see http://www.dilwyn.me.uk/asm/deafree.zip

Basically, I have now got a copy of "The Designer" from Pyramide which is a CAD type program.

Whilst looking at its files, I notice that as part of its installation routine, it asks if you are running a French QL? If so it then installs a patch for the French MG ROM - the patch can be found at:

http://www.rwapsoftware.co.uk/downloads/MG_FIX

This is just LRESPR'd into memory.

What does it do though?

The manual says it fixes a bug in the French ROM.

The MG ROMs (I have a german one with the same problem) have a nasty problem with the SD.POINT routine that draws single pixels: They always draw 2 pixels instead of one, the 'shadow' pixel being of different colour and slightly offset from the real one. The same problem exposes in the SuperBASIC POINT routine. You couldn't reasonably use pixel-based graphics on them, there was always a slightly odd look in your pictures.
The "MG patch" is expected to fix this. If I remember right, just installing PE also fixed it.

tofro wrote:The MG ROMs (I have a german one with the same problem) have a nasty problem with the SD.POINT routine that draws single pixels: They always draw 2 pixels instead of one, the 'shadow' pixel being of different colour and slightly offset from the real one. The same problem exposes in the SuperBASIC POINT routine. You couldn't reasonably use pixel-based graphics on them, there was always a slightly odd look in your pictures.
The "MG patch" is expected to fix this. If I remember right, just installing PE also fixed it.

I think that the Toolkit 2 patches this - there is a reference in the TK2 updates list (v2.03) about a patch to MG ROM initialisation problems, although I am not sure if this refers to the point bug or the when error flag resetting.

Dilwyn

dilwyn wrote: I think that the Toolkit 2 patches this - there is a reference in the TK2 updates list (v2.03) about a patch to MG ROM initialisation problems, although I am not sure if this refers to the point bug or the when error flag resetting.
Dilwyn

Yes, you're right - It was actually TK2 that fixed it. Been too long I wasn't remembering correctly.