Search found 1964 matches

by tofro
Tue Jul 21, 2020 5:32 pm
Forum: The Off-Topic Section
Topic: Today I Received...
Replies: 271
Views: 28163

Re: Today I Received...

OK, not quite today but a few days ago... I got a replacement B&W TV/Radio for the one my Dad got rid of during one of his "clear outs" in the mid-1990s, The same model as we used to have. I've spent the last couple of days cleaning it inside and out, removing 30 year old smoker's tar...
by tofro
Tue Jul 21, 2020 2:20 pm
Forum: Hardware
Topic: Screen noise when using microdrives
Replies: 8
Views: 570

Re: Screen noise when using microdrives

I also see stuff like that, but have never seen it on an unexpanded QL. As Marcel says, it seems to be a loss of alignment between the SGC video shadow and the "real" video memory in the QL. Can you run the Minerva memory test on this QL? It nearly looks as if the video memory on that mach...
by tofro
Tue Jul 21, 2020 10:25 am
Forum: General QL Chat
Topic: What makes the OS for QL any better, different, unique ?
Replies: 80
Views: 8255

Re: What makes the OS for QL any better, different, unique ?

Well, computers nowadays aren't being designed for programmers, but rather for end users.

And, properly written applications assumed, there shouldn't be any noticable difference from an end-user's perspective between a pre-emptive or cooperative design.
by tofro
Mon Jul 20, 2020 8:12 am
Forum: Software & Programming
Topic: Prospero Pascal BEEP
Replies: 16
Views: 1341

Re: Prospero Pascal BEEP

Turtle graphics are not part of QDOS - They are implemented by the SuperBASIC interpreter. If you want them in Pascal, you'll need to implement a library (nice little educational task, btw). RESTORE, READ and DATA are "interpreted-language constructs" and are entirely not needed in Pascal ...
by tofro
Wed Jul 15, 2020 1:08 pm
Forum: Help for New Users
Topic: Floppy drives misbehaving
Replies: 7
Views: 716

Re: Floppy drives misbehaving

The floppy controller itself failing is the least probability - There's not many functions on there that are drive-specific (that is, the main part of the function is shared between all connected drives) - It is much more likely that your floppy cable (or its connectors) is at fault, as that has bee...
by tofro
Wed Jul 15, 2020 7:53 am
Forum: Help for New Users
Topic: Floppy drives misbehaving
Replies: 7
Views: 716

Re: Floppy drives misbehaving

To determine if its a software or hardware problem what you see: What happens if you do a straight "dir flp2_" ?

Tobias
by tofro
Tue Jul 14, 2020 4:22 pm
Forum: Hardware
Topic: SGC and mystery sound
Replies: 3
Views: 486

Re: SGC and mystery sound

That's the "your disk is dying" requiem.

(S)GC sings this on disk read errors.

Tobias
by tofro
Mon Jul 13, 2020 8:05 pm
Forum: Hardware
Topic: puzzled cst qdisk interface
Replies: 8
Views: 1070

Re: puzzled cst qdisk interface

There's a pretty nice description in the QL Technical guide on how expansion cards need to handle requests (Chapter 11.3, "Adding peripheral cards"). That involves address decoding logic and a fast switching transistor - This is the circuitry you should look into.
by tofro
Sun Jul 12, 2020 3:20 pm
Forum: QL Emulation
Topic: How to uQLx on RPi
Replies: 29
Views: 1683

Re: How to uQLx on RPi

Well, sortof: You can run native Linux programs from within uqlx using the pty interface (see the uqlx manuals for details). There should be some Python scripts in Raspbian that allow you to fiddle with the GPIOs - But don't expect wonders with regards to the speed: You will not be able to crate a 5...