Just one correction:

Replace "Zange" and "Greifzange" with "Greifer"

And propose to change "R", "S", "L" with "Gelerntes Programm ausführen"/"abspeichern"/"laden"

In addition to this RtL, Arabic characters change their shapes based on their positions in words. For example, a character such as م can be at least written in 4 different shapes (isolated, initial, middle & end)!

Arabic is indeed a complicated language. Proper Arabic support on modern computer also needs to support diacritics, where characters change their shape according to their neighbors (that was apparently what you meant).
The Sinclair ZX Spectrum actually was available with an Arabic ROM as well, supporting RTL writing, but no diacritics. It's fun to at least try that out in an Emulator (Right-toLeft BASIC programs do look weird!). The ROMs are available from WoS.

Tobias

The Sinclair ZX81 in kit form, when it was released in 1982, was GBP 99.99 - an unbelievable price for an unbelievably non-computer.

Compared to that, the EP was cheap at GBP200 two years later.

Tobias

Are there any German members here? Do you feel the following senteces correct? I mean the last word at the end of each line (eins/welche, keinen, eine/welche):

Wir haben kein Brot. Geh und kauf eins/welche.
Möchtest du Tee? - Nein, ich trinke keinen.
Öffne das Fester! Ich brauche Luft. - Auch ich brauche eine/welche.

This is obviously a test for non-countables' pronouns. Bread, tea and air are (can be, "Brot" can be an exception if you mean a specific loaf of it) non-countables - here "Stoffbezeichnungen" -  in German that go with indefinite pronous.

Wir haben kein Brot. Geh und kauf welches. (you mean the uncountable thing, the concept)
Wir haben kein Brot. Geh und kauf eins. (You mean "one loaf of it". Could be considered colloquial)
Möchtest du Tee? - Nein, ich trinke keinen.
Öffne das Fester! Ich brauche Luft. - Auch ich brauche welche.

What would be current options for a (moderate, 512k-1M) internal RAM expansion? I understand Saint's board is no longer available.

Thanks, Tobias

Some USB/Serial dongles don't support hardware handshake lines at all, some do RTS/CTS, some very sophisticated ones even support DSR/DTR. For those that support the hardware lines, you need to have a proper driver that supports hardware handshake as well (The USB stick needs to convert the pin change to a USB handshake packet and send that to the host and vice versa)

So, the first questions is: Does the chipset on the dongle support hardware handshake? The most common chips known to do that are FTDI USB/Serial chips. In case your dongle has one (and not a cheap Chinese rip-off), chances are high it works.

Another common chip range is the Prolific 2303 - Of these, only the SA, HXD and RA variant seems to support hardware handshake. The others don't (Those are mostly intended for printer interfaces only).

That is the first step to success - The next one is if the Dongle maker managed to expose the hardware handshake lines from the chip - Some do, some don't.

And the next step is whether you got a proper USB driver on the host computer that supports Hardware Handshake. Again, some do, some don't.

Best check very carefully the above points in the product description before you buy such a dongle to get HWHS to work

Tobias

I was in your situation some months ago and my favourite storage would have been the SD card interface. I have repeatedly tried to contact SzörG who used to make them, but he doesn't seem to produce them any more.

My second best choice was a disk interface, I now have one of pear's EXOS cards (here) and am entirely happy with it (Maybe not as happy as with an SD card, but happy enough). I use the EXOS card with a dual "real" floppy drive, but a HxC wouldn't be much different.

It would be nice if someone could be persuaded to produce a number of new SD card cartridges.

Tobias

Brilliant!

Nice to see how an 80ies CPU would have struggled with tasks we consider "minor background processing" on modern computers.

Thanks!