64, not 640.
Well, 16 KB - 256 KB, with a directly addressable 64 KB and a segmented architecture to reach further.
I had one of these in mid 1982 to late https://en.wikipedia.org/wiki/IBM_Personal_Computer
And it included a cassette interface.
alt Hacker News
Well, 16 KB - 256 KB, with a directly addressable 64 KB and a segmented architecture to reach further.
I had one of these in mid 1982 to late https://en.wikipedia.org/wiki/IBM_Personal_Computer