[Doctor_Fegg]

Everything was in ROM: 16k BASIC, 16k operating system, optional 16k disk operating system. The 464 (“646” is a typo) shipped with a cassette deck, not a floppy disk drive, so there was no possibility of loading the OS from volatile storage.

[masswerk]

> so there was no possibility of loading the OS from volatile storage.

There are exceptions to this rule: Sharp was known for their concept of "clean computers" (MZ series and X1), which came only with a simple monitor in ROM, while at the same time featuring just a cassette drive to load a BASIC interpreter (of which there were several flavors) from.

[ikari_pl]

And Amstrad PCW had boot code in the printer controller, to save on ROM prices :D, and booted from a floppy only (by default to a CP/M as well)

[sedatk]

You could attach an external floppy drive (I believe it was called FDD-1) to CPC464 and run CP/M 2.2 on it. https://www.cpcwiki.eu/index.php/CP/M_2.2

[Doctor_Fegg]

DDI-1. It was a package including the disk interface (with AMSDOS in ROM and CP/M 2.2 partly in ROM) plus the drive itself. The FDD-1 was an optional second drive but you had to have the DDI-1 first.

[CJefferson]

They could have typoed '664', which was the 464 with a floppy disk drive. However there basic was still in the ROM.

[ghusbands]

It was a typo for 464 - you can tell by the video it links to.

[Doctor_Fegg]

Indeed. I still have my 664 in the loft somewhere!

[UncleSlacky]

They're worth quite a bit these days as they were rapidly replaced on the market by the 6128 (which is in my loft).

[CJefferson]

Wow, I had no idea! There might be a 664 in box in my parent's house somewhere -- although it also might have been discarded some time in the last 20 years (as I imagine happened to many of them).