Maury Markowitz
  • Member for 5 years
  • Last seen this week
Why does the Cray 2 use 400 Hz power, and why generate that from motors?
Accepted answer
47 votes

The reason for any higher frequency supply is almost always the same: you get to convert a single input to different voltages for less wasted heat in a smaller volume. Such systems were very common in ...

View answer
Cartridge modems - was the Vic-20 a special case?
3 votes

The Atari's originally included a 12V feed that was passed out through SIO and could be used to drive RS-232. I think the only product that ever used it was the 835 modem, but I'm not sure, it might ...

View answer
How did Apple fail to tap the business and scientific markets?
7 votes

I would say that the Apple II did tap the business and scientific markets! From the business side, VisiCalc on Apple II was a major driving force in many businesses. One could make the case that it ...

View answer
MITS to Dell: the mail order gap?
9 votes

Why did nobody between MITS and Dell make it big purely in mail-order sales? The Sinclair ZX81 neatly refutes your statement. But more broadly, your claim depends entirely on your definition of "big"...

View answer
Looking for an "Inspector" or "Detective" game (BASIC?)
1 votes

Nothing like this game appears in 101 BASIC Games or any of its descendants like More BASIC Computer Games. I can't find anything like it in What To Do After You Hit Return. Nor is it in Announcing: ...

View answer
640x480 color display in 1980
5 votes

You could buy such a system off the shelf in (late) 1980. You needed a large-ish S-100 machine like a Horizon, and a couple of MicroAngelo cards. Each card held a single bitplane of 512 by 480. You ...

View answer
CP/M in less than 80 columns
3 votes

The original video displays for S-100 machines were normally 64x24 or 25. Practically every machine used this mode. 80-columns did not appear until well after CP/M was widely used.

View answer
What caused the demise of BASIC/BASICA in the late 1980's?
3 votes

And I'll go in another direction... I think the main reason BASIC was ever "popular" on micros was not that everyone wanted to program, but that there was no other way to cheaply distribute software. ...

View answer
Is emulation ultimately the future of retro computing?
6 votes

My question : Is emulation ultimately the future of retro computing ? No. Not any more than emulating a 1960s Mustang with a Beatle mod is the future of retro cars. Easier? Sure! Totally useful? ...

View answer
How to create a switchless multi-system 2 button Atari joystick?
3 votes

Furthermore, (correct me if I'm wrong) the Commodore Amiga can also read a joystick button wired this way being pushed, as although it treats pin 9 as an analog input, the Amiga's analog pins are ...

View answer
How were files transferred between different systems in the late 1980s?
-1 votes

The 8-bit machines were mostly (in numbers at least) used non-professionally for home use. I found that most of the files from those machines found their way onto bulletin board systems. Much of that ...

View answer
Can we express the instructions to the Analytical Engine in terms of assembler or machine code?
Accepted answer
9 votes

Yes. In fact, it is a very simple system in machine language terms. The key to understanding the system is to look at the physical construction of the part you saw. This is what we would today would ...

View answer
Was the design of MS-BASIC for 6502 based on MS-BASIC for 8080?
2 votes

The original Altair BASIC came in three versions; 4k, 8k and Extended. The numbers referred to the amount of RAM required to run it, as BASIC was loaded to RAM from paper tape. The 4k version running ...

View answer
What was the 2nd best selling computer ever?
9 votes

Commodore famously inflated their sales numbers, so while you'll find many resources claiming 25 or 30 million 64's sold, it appears the number is closer to 17 million. Behind that are two machines ...

View answer
Differences between 4k, 8k and Extended Altair BASIC?
Accepted answer
9 votes

And I found the answer only moments later when I came across the original manual. The difference is that the 4k version (mainly) did not have strings (!!), lacked a number of math functions (ATN, etc),...

View answer
Why were early versions of BASIC different?
10 votes

I'll speak to the Atari BASIC issue. MS BASIC for the 6502 was ported directly from the original 8080 code. On the 8080, the code was well under 8 kB, which allowed the complete BASIC interpreter and ...

View answer
What implementations of BASIC had a robust flood fill operator?
3 votes

Atari BASIC had a fill operation, but for some reason this was not mapped to a command called FILL, but instead one called XIO. The background here is that they couldn't fit the BASIC into an 8k ROM. ...

View answer
Why did the Atari 800 designers choose such a radical system design?
3 votes

I'm pretty sure the main reason for the slots was to keep the cards vertical, for cooling purposes. Airflow went straight up the slots and out the top. In theory, they could have implemented this ...

View answer
Can a PET 2001 be physically damaged from BASIC?
1 votes

The computer lab at Bradford District High School consisted of about eight PET 4032's connected to shared printers and disk drives. Every so often the "killer poke" would come up, the last time I ...

View answer
Who wrote the MS BASIC on the PET/C64/etc?
-1 votes

It turns out Monte did not work on the 6502 version, but pointed me in the direction to figure all of this out. The A% format originates not in MS BASIC, but the one they based it on, BASIC-PLUS on ...

View answer
Which pointing devices were used by early laptop computers?
2 votes

The Outbound was a Mac clone in a laptop form factor. It used a unique pointing device consisting of a small rolling cylinder that controlled the up-and-down motion and could be forced sideways ...

View answer
PET space arcade game with surprisingly good graphics
Accepted answer
12 votes

And it's definitely Star Spores. I found an interview with the author, who it turns out lives fairly close to me, and he mentioned the line-drawing routine which I'm sure is referring to the lightning ...

View answer
Game cartridges on the S-100 bus?
1 votes

The Exidy Sorcerer did exactly that, it had a cartridge format known as "ROM-PAC" that was simply a subset of the S-100 pins arranged in a slot at the rear of the right side of the case. This was a ...

View answer
Were there any "off the shelf" graphics chips that supported 2D sprites in the 70's and 80's?
2 votes

The graphics chip developed by Nutting for Bally was used in many of their arcade games as well as the Astrocade console (ostensibly from Bally, but not really) and the Datamax UV-1. It did not have ...

View answer
What file systems / encapsulation formats used ASCII?
6 votes

The codes in question were normally used to simulate special interrupts and/or control cards. The idea is that you could take a stack of 80-column punch cards (for instance) and translate them as a ...

View answer
1 2
3