The Sinclair QL Forum

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Sure you have a 640 K internal memory epansion!

I have never heard of it. Internal memory expansion normally had a total of 512 KByte (and you have to send it to a company which fitted the upgrade). Disadvantage: It was slow memory, cause also the video hardware ("processor") accessed ...

Interesting that there's still ISDN in the UK. I had ISDN until 2010, when I migrated to fiber (having had DSL for my internet connection since 2002 and cable internet since 1998).
In Holland, ISDN has been discontinued since a few years, and POTS is also rapidly being dismantled.
(My town was ...

Are the old modems still usable today?

Probably only if you have a PABX to connect it to your other modem.
Online services offering dial-in have almost vanished (except maybe some die-hard BBs), and analogue phone lines are rapidly replaced by DSL and fiber connections. The voice service runs ...

I did some investigation, tracking back the seller of this QL on ebay. There was a second auction from the same seller where the
"Sinclair QL EPROM Cartridge Board with an EPROM labelled 13-2-84 8000 0D0C as checksum" was sold. Most likely this would fit to this QL computer with the ZX-83 PCBA ...

Such a shame that the missing third will remain missing unless the owner of the dongle ever realises and sees this thread.

The jump table into the $C000 range suggests that there should be some code there. But how do you get code there if the ROM port is already occupied by the 'missing' 16K at ...

At first sight, this doesn't look like a production ROM. The locations from $00C0 onwards contain a jump table, pointed to by the various exception vectors, and the targets of the JMPs are in the $C000-$C08C range (i.e. ROM dongle!). This also means that the vectors starting at $00C0 are missing so ...

I remember writing a date routine for ctime to readable date using PL/1 - but I've long since lost that source code.
The basic premise is that every 4 years is a leap year, except every 100 years, except every 400 years - the year 2000 is a leap year.
Once you have that, it's just a matter of ...

The 24H2 update installed 'Recall', it can't be uninstalled. Recall takes a screenshot of your desktop every so often, ocrs it into a Sqlite database which has around zero security protection. It might be sent to Microsoft but don't quote me.

Shouldn't that be Windows 11? I cannot find anything ...

It would have been better to omit the IPC completely, attach keyboard and beeper the Spectrum way and save time-to-market, board space and costs. Just one serial port in that case, but a decent one.

If they would only have implemented a proper UART, not the bit-banging of the ZX Interface 1 ...

Which version is your SGC ROM? As mentioned in the README, it was tested with v2.49 which is AFAIK the latest version for both GC and SGC. Older versions may not work, since the code very much depends on the entry point in the (S)GC ROM.

Also, be sure that your QL ROM image is exactly 49152 bytes ...