The Sinclair QL Forum

This is basically how the SGC works, but it manipulates the decoder. [Explanation of SGC snipped] Ahem... the whole point of my idea was not to implement decoding, mapping and bus sizing as complicated as the SGC. ;) I know, but you have to implement 90% of it or more, anyway. I.e. once it gets int...

This is basically how the SGC works, but it manipulates the decoder. Without some sort of mechanism like this, it is impossible to implement different OS's because the exception vectors and vectored OS routines need to be changed when the OS is changed. There are many mechanisms to implement this. A...

TBH I don't exactly remember how slaving is used in the old drivers. I do remember that originally the slave block table was limited to 32k in Minerva due to a bug, but that was soon fixed (word index was used). I seem to recall there is some sort of linear search, initially? Is this what limits the...

After discussions, the memory map is provisionally as follows (as of two days ago): $000000 - $BFFFFF 3x 4MB banks - 12MB $C00000 - $DFFFFF Flash $E00000 - $FFFFFF Aliases of original QL map. Screen: $20000..$27FFF on the QL bus, which appears to the CPU in this proposed system at $E20000..$E27FFF ...

VESA compatibility was really my first worry. There is really no shortage of monitors with VGA input (yet :) ) but monitors as such are getting dumber by the model. Already a few years ago when I was designing some gaming hardware (for casinos), we had big problems with monitors that would not corre...

I would definitely vote for a stand-alone version. Also, regarding HDMI, there are still HDMI transmitter chips available that do not require royalty for the data encription/protection, IIRC Ti makes them. I have had a look at the board and something like an unpopulated set of pads for a header dire...

A bit of barking up the wrong tree in this thread. There is no simple way to get the flash bit converted into a fourth color bit using the signals the QL outputs in mode 8. However, with a fair bit of circuitry, it is possible to get it out of mode 0/4. The tricky part is getting the dot clock, whic...

You can't directly connect QL microdrives to the port because a part of the necessary circuitry to make an internal unit to an external one is on the QL motherboard. However, one could build that part up on a small board with the appropriate edge connector and use an internal unit as an external one.

Hi Nasta, Thank you for the clarification, I did think a standard QL with a memory expansion would be able to run SMSQ/E. But from your description, it seems the best solution would be to have an Aurora. Pity the Aurora, is not available anymore. Mind you, it could be done with a RAM expansion that...

There is a difference between physically 'paging out' a physical memory chip and not using that part of the memory map. In fact, the way the (S)GC does it is to _replace_ the physical ROM chips with a copy (somewhat patched) contents of the ROM but in the same address space. In essence, it emulates ...