CP/M and DOS

Moved from Wish Lists…

Is QBASIC actually built-in and always available

QBASIC present from MS-DOS 5.

As to “built in”, that’s not really answerable. It was supplied with the installation, it could be present, and it was on disc. But then so was the entire rest of the system. The only bit in ROM was the BIOS and the painfully simple bootloader.

how A Mess DOS edged CPM out, I’ll never understand.

Three reasons.

1, The DOS command interpreter contained several of the common commands directly within itself. On older floppy systems (back when CP/M was a thing), this made DOS a lot faster as it didn’t have to find the program and run it.

2, DOS was the OS supplied with the shiny new IBM, because Gates could see what IBM couldn’t. The whole thing exploded and sent DOS into the mesosphere.

3, DOS cost about $40-60. CP/M-86 cost about five times more. Both essentially did the exact same thing (as far as users were concerned, given that DOS borrowed heavily from CP/M).

It’s worth noting that IBM actually tried to get CP/M first, but Digital Research (the home of CP/M) didn’t like the deal so they walked. Gates turned up with something similar, cheaper, and by a master stroke managed to get the deal set up that they were the sole suppliers of the OS to IBM, but they also had the right to supply it for non-IBM kit. IBM, historically never really taking the PC entirely seriously, agreed.
The rest is history.

Massive mistake by Digital (they could have been the innovators, not Microsoft), and everybody knows how badly IBM misjudged because they were still fixated on Big Iron and simply couldn’t conceive that people might want their own little computer. While the first PC was released in 1981, it wasn’t really a part of the home computer boom of the early 80s because of cost and complications. That was a lot of Z80 and 6502 hardware, as we Brits know only too well. ;)

But as the price of memory dropped, the humble PC started to come to the front. The same PC that came with 16K of memory could ultimately be upgraded to 640K (some on the motherboard, some on an expansion card). It also supported multiple monitors (one could have MDA and CGA cards and use both at the same time – some software such as AutoCAD did). And the expansion slots, later to be known as the ISA bus, had many things built for it.

So while new machines turned up (Amiga, Archimedes, Mac…), that same old PC from 1981 could be given a new lease of life with cheaper memory and so many plug in widgets your head would spin.

And DOS was there all the way. CP/M became a mostly forgotten relic.

Just a quick correction Rick:

As to “built in”, that’s not really answerable. It was supplied with the installation, it could be present, and it was on disc. But then so was the entire rest of the system. The only bit in ROM was the BIOS and the painfully simple bootloader.

This was true for PC clones (which historically started from the work of Compaq and Phoenix). However IBM PCs did indeed had a BASIC interpreter in ROM, IIRC it was called “Cassette BASIC” and would start automatically if no DOS was booted.

For reference here, more info: https://en.wikipedia.org/wiki/IBM_BASIC#:~:text=IBM%20Cassette%20BASIC%20came%20in,an%20operating%20system%20to%20run.