Riging together a way to store data on an audio cassette

[MikeH]

Originally posted by reds4ever

MikeH: IIRC the C64 tape deck used to operate at 600 baud and then veify the data, making it effectively 300 baud.

If that's a criticism of my loading impression then I don't know enough geeky technical sh1t to know what it means.

[reds4ever]

It would have been clearer if I'd have spelt 'verify' correctly, any better now??

[MikeH]

Nope. Definitely not.

[DanS]

I remember that my dad and mom spent a fortune on the C-64, 1541 disk drive, Epson printer, monitor, and word processing software. $1,500 in 1983.

This was big bucks at the time ($3,000 in today's money) and my dad had a heart attack a year later. Coincidence? Maybe not.

[Harovan]

I paid 2500 East German Marks for an Atari 800 XL basic device in 1986. It was somewhat risky, because as professional soldier I was not allowed to make such transactions. No printer, no disk drive, not even a datassette, which led to our "turbo" development described above, together with an electronics specialist, who made the hardware and (very important) fitting plugs. I think if I dig deep enough in my papers, I'd even find the driver code, written in 6502 assembler.

But the software was dirt cheap. There were enough cracked modules out, we made tape files from them and copied freely each from other, completely safe from persecution behind the iron curtain. I had more than 100 games and scores of useful programs like compilers (even Fortran), assemblers (several), word processing software (pretty useless without printer) and even a star catalogue.

[alva]

I paid 2500 East German Marks for an Atari 800 XL basic device in 1986.

You rich communist ******...I only had the 600XL.

Of course I had it several years earlier at the age of 12-13 and was able to buy it from my allowance.

Learned my first lines of code on that one.

[reds4ever]

Originally posted by alva

I paid 2500 East German Marks for an Atari 800 XL basic device in 1986.

You rich communist ******...I only had the 600XL.

Of course I had it several years earlier at the age of 12-13 and was able to buy it from my allowance.

Learned my first lines of code on that one.

600XL, did nt that pooter have the best keyboard ever?

[alva]

It's the same as the 800XL, the only difference that I can remember was the memory.

[reds4ever]

Originally posted by alva
It's the same as the 800XL, the only difference that I can remember was the memory.

yep 16 against 48, i used to own one, the thing I remember is the keyboard, it was spot on.

I wrote a version of the Vic 20 game Blitz on it, ah, those were the days....

[Harovan]

Actually, the 800 XL had full 64 KB, not only 48. Of these 64 KB, 16 were hidden, because the OS ROM was set on the same addresses. 8 more were hidden, when the BASIC interpreter ROM was active. But this RAM existed and could be accessed by disabling all interrupts (obviously) and then temporarily turning off the OS ROM, which was possible. the 16 KB we used for several purposes. So we had for instance a RAM disk solution. Even alternative OSes with more features existed, which could be loaded from tape, moved into the RAM "below" the original OS, which then was disabled so that the alternative OS could work.

[alva]

OK, all I did with it was:

input a
input b
print a+b

[reds4ever]

You're quite right Sir Ralph, it was 64K, IIRC the idea behind the BASIC was that you could disable it and use another language instead (it was on a cartridge on the 400 and 800), the concept never really took off.

What was it called when you could use the time when the raster(?) on the TV went from bottom right to top left to put extra sprites on the screen?

[DanS]

I think if I dig deep enough in my papers, I'd even find the driver code, written in 6502 assembler.

Props.

Why on Earth they ever forbade such things is beyond me.

[reds4ever]

Originally posted by DanS


Props.

Why on Earth they ever forbade such things is beyond me.

'Cos only the guy who wrote the code knew what the hell was supposed to be going on.

Anywho the 6502 was sh!it the Z80(a) was the mutts nutts

[Harovan]

Originally posted by reds4ever
You're quite right Sir Ralph, it was 64K, IIRC the idea behind the BASIC was that you could disable it and use another language instead (it was on a cartridge on the 400 and 800), the concept never really took off.

What was it called when you could use the time when the raster(?) on the TV went from bottom right to top left to put extra sprites on the screen?

Vertical blank interrupt, once every 20 milliseconds. There was also a horizontal blank interrupt at the end of every screen line, which could be used to switch graphics modi and screen colors, quite effectful.