The Sinclair QL Forum

Peter wrote:So do I understand correctly, that your peripheral (e.g. IDE or SDHC) speed calculations are excluding higher OS levels?

Yes. LBYTES/SBYTES is close to raw read/write.

Was the "about 1.8M/sec" absolute maximum figure including or excluding higher OS levels? Is this actually reading a file to RAM? If the SGC could actually read a file under SMSQ/E at that speed - regardless how well implemneted the hardware interface is - I would be surprised. The theore...

The only point I could see for SATA on a system like this would be CDROM access. If it had to be implemented, it would probably be via IDE-SATA interface. This is the idea exactly. But the right bridge chip has to be chosen, some do not support CD ROMs. On the other hand, all of them support hard d...

Since the thing is SRAM based, memory expansion requires the full address and data line set. This is not going to be on the expansion connector, nor should it, the signal speeds there are far too critical and fast, This remains local to the CPU and is not seen on outside buses. If it is expandable, ...

Also for identical devices, separate SPI interfaces are important in case of different drivers. For example, think of copying from a QLWA formatted SDHC card to a Qubide formatted card, if one driver is built into SMSQ/E and the other one is separate. This is one reason why the Q68 has separate int...

- Implement a simple compression algorithm for SMSQ/E modules. They are copied from ROM to RAM anyway, so why not uncompress them on the fly... Marcel Good idea for any code that is not executed from it's original storage... BTW thanks for the data on ROM space protection, if anyone should know... :)

Just a short return to the original topic: After some peering into the various datasheets: 70ns static RAM will just barely do zero wait state on a 68EC020 up to 25MHz. 55ns static RAM can do zero wait up to around 33MHz. In theory some MHz can be had by decoding the RAM slightly differently. The th...

Not to spoil the fun, but what exactly do you intend to connect a serial port to? Especially at higher speeds than 230400? Let's not nix up our serial ports. Standard serial RS232 has little to no resemblance to I2C or SPI. The latter are intended to be local (short distances, centimeters) and relat...

Peter wrote:

Peter wrote:BTW I will soon add 8 Bit Aurora mode in 1024x768 to the Q68.

Just for info, I'm reconsidering this, because it turned out to bloat SMSQ/E size a lot.

As far as i have seen, isn't there 32M of RAM on board? I am sure SMSQ/E still remains tiny compared to today's standards...

1024x768 in 4 colors was the most requested mode when I was developing Aurora :) and probably most used too on LCD monitors. I suppose it would take about 5% of the available bandwidth which is negligible. I suppose you use page mode to access and then FIFO buffer the video data since these are stri...