3 ms·

> It could also have been the case that Microsoft did not have an operating system or BASIC ported to the Motorola 68000 architecture. The late 70s / early 80s

> It could also have been the case that Microsoft did not have an operating system or BASIC ported to the Motorola 68000 architecture. The late 70s / early 80s incarnation of Microsoft was happy to port their software to just about anything, so long as there was a customer willing to pay for it. If IBM had asked Microsoft for a 68K OS instead of an x86 one, Bill Gates would have found a way to provide. He bought PC/MS-DOS from another company, he probably could have found someone selling a 68K OS instead. Or Tim Paterson surely could have ported it to 68K if asked. I think choosing the 8088 over 68K was all about hardware costs, not software-both the cost of the CPU, and the cost of compatible peripheral chips.

aidenn0 4y ago
I don't have a source handy, but I remember reading it was because the 68k was too late to production; it was scheduled to be ready on time, but the Intel parts were already available, and IBM didn't want the risk
- freitzkriesler2 4y ago
  An alternate timeline where 68k was the dominant OS architecture? Man what a fun thought experiment. Reminds me of Palm OS and their OS5 68k emulator on top of arm.
  - snvzz 4y ago
    OS architecture? Not ISA architecture?
  - skissane 4y ago
    My own thought experiment - what if “old IBM” had intervened in the product and tried to make it more “IBM”. Well, if they’d done that too much - e.g. a corporate edict that it had to use EBCDIC instead of ASCII - that probably would have killed it commercially. But what if “old IBM” had just demanded ASCII-EBCDIC conversion in the BIOS? With a “code page” field in each directory entry, which could be used to mark files as ASCII or EBCDIC (0=binary), with the BIOS ASCII-EBCDIC conversion service invoked to make EBCDIC files appear as ASCII to applications? That might have made the product more “interesting”, without adding so much complexity as would kill it. z/OS Unix has code page tagging in the filesystem; apparently IBM tried to get it added to DOS during DOS 4 development, but it got pulled before release (although that was not for EBCDIC, just for tagging which ASCII code page a file was) Maybe even demand some optional record-oriented support in the filesystem (e.g RECFM=F80). That would have been less alien to Microsoft than you’d think, because Microsoft BASIC always supported record-based file access.
zabzonk 4y ago
> and the cost of compatible peripheral chips. particularly this, i think, and also availability.

aidenn0 4y ago

I don't have a source handy, but I remember reading it was because the 68k was too late to production; it was scheduled to be ready on time, but the Intel parts were already available, and IBM didn't want the risk

freitzkriesler2 4y ago
An alternate timeline where 68k was the dominant OS architecture? Man what a fun thought experiment. Reminds me of Palm OS and their OS5 68k emulator on top of arm.
- snvzz 4y ago
  OS architecture? Not ISA architecture?
- skissane 4y ago
  My own thought experiment - what if “old IBM” had intervened in the product and tried to make it more “IBM”. Well, if they’d done that too much - e.g. a corporate edict that it had to use EBCDIC instead of ASCII - that probably would have killed it commercially. But what if “old IBM” had just demanded ASCII-EBCDIC conversion in the BIOS? With a “code page” field in each directory entry, which could be used to mark files as ASCII or EBCDIC (0=binary), with the BIOS ASCII-EBCDIC conversion service invoked to make EBCDIC files appear as ASCII to applications? That might have made the product more “interesting”, without adding so much complexity as would kill it. z/OS Unix has code page tagging in the filesystem; apparently IBM tried to get it added to DOS during DOS 4 development, but it got pulled before release (although that was not for EBCDIC, just for tagging which ASCII code page a file was) Maybe even demand some optional record-oriented support in the filesystem (e.g RECFM=F80). That would have been less alien to Microsoft than you’d think, because Microsoft BASIC always supported record-based file access.

zabzonk 4y ago

> and the cost of compatible peripheral chips. particularly this, i think, and also availability.