Re: Did Commodore cheat with the quad density floppies?

On Tue, Jan 15, 2019 at 03:23:59AM +0100, Mia Magnusson wrote:
>>They then took their old 8080 based motherboards and adapted them for 
>>8088, CPM-86 came out but then so did MSDOS.
>
>That might had been true in North America and Japan but not always in 
>Europe. Afaik for example Ericsson and Nokia never made any CP/M 
>computers or any computers at all before their first 8088 "DOS" 
>computers.

The 2 first models of the Nokia MikroMikko series were not IBM PC 
compatible. The MikroMikko 1 ran CP/M on 8085 and had a monochrome 
display. The MikroMikko 2 (which I do not remember ever seeing) ran 
MS-DOS on 80186.

At school, I got first-hand experience from the MikroMikko 3, which was 
running on 80286. I think that it was pretty well built, even featuring 
remote control (viewing the screen or taking over the keyboard) from the 
teacher's unit. The student workstations were equipped with two 3.5" DD 
drives, while the teacher's unit had a hard disk and 5.25" HD and 3.5 DD 
drives. I think that the computers were only connected by the keyboard 
and display switch; I do not remember anything like Ethernet. The 
machines were originally running MS-DOS 3.21.

https://en.wikipedia.org/wiki/MikroMikko

>Anyway in practice you'd mainly need a PC compatible BIOS (and
>reasonable allocation of some of the interrupts) to run many of the PC
>programs, and with PC compatible display hardware you could get away
>with running almost all PC software even if every other part of the
>computer, of course except the CPU, were incompatible with the PC. (As
>the PC BIOS did totally suck re the serial port routines, all terminal
>software and similar of course actually required an 8250 or 16550 at
>the well known addresses and using the well known IRQ's).
>
>The display hardware also only had to be compatible at the video memory
>level, not that much at the I/O port level.

I agree on this. I never encountered any compatibility issues with the 
Nokia MikroMikko 3, but then again, my use of RS-232 was limited to 
plugging in a mouse, and the computer only supported EGA or VGA level 
graphics. I cannot even remember if I tried to run FractInt (and some of 
its custom graphics modes) on those machines.

	Marko