Did they punt the 6847+SAM in the COCO3?
Dick
----- Original Message -----
From: "Tony Duell" <ard_at_p850ug1.demon.co.uk>
To: <classiccmp_at_classiccmp.org>
Sent: Wednesday, April 24, 2002 4:26 PM
Subject: Re: Micro$oft Biz'droid Lusers (was: OT email response format)
> >
> > I haven't looked at the insides of the COCO2 I've got sitting here, but I
> > don't see any place for a FDD or a HDD. Are there serial ports anywhere
that
>
> On the right hand side of the main PCB is an edge connector, officially
> called the 'cartridge port'. Although originally designed for ROM
> software cartridges, it's essentially the 6809 system bus, and you can
> connect an FDC or HDC here (both were sold by Radio Shack, BTW)
>
> As for serial ports, there's a bit-banger built into the machine (it's
> the 4 pin DIN socket on the back of the PCB). As a bitbanger, it's best
> used for output only (to drive a serial printer, for example), but I used
> OS-9 as a 2 user system with a 300 baud terminal connected there for a bit.
>
> More reasonably, you'd connect an 6850 or 6551 to the cartridge
> connector. There was a Radio Shack cartridge to do this (also containing
> a dumb terminal emulator in ROM). Hardware hackers built multiple serial
> port cartridges, particularly if they ran OS-9 seriously.
>
> There's also a think called a Multi-Pak interface that connects up to 4
> cartridges at the same time. It was common to use one of these to connect
> an FDC, HDC and serial cartridge to the CoCo.
>
> > I can use? How much R/W memory does it have? How do you expand it to do
>
> CoCo 1 : 4K, 16K, 32K (or 64K with simple mods)
> CoCo 2 : 16K or 64K
> CoCo 3 : 128K or 512K
>
> > something useful?
> >
> > ... see what I mean? You have to do so much to the thing that RS sells
you
> > that it takes up a whole tabletop just to get to what's in the PC's box,
and
>
> Well, the fact you can buy it in sections is actually an advantage if you
> can't afford it all at once. I bought the CoCo first, then the disk drive
> and OS-9 about 6 months later. And I then built my own multi-pak
> backplane and serial ports.
>
> And it's not impossible to repackage the CoCo into a PC-clone case.
> Plenty of people did.
>
> > The worst you have to do with a PC, PDP11, or whatever computer you buy,
is
> > plug in what you want to use.
>
> Ditto with the CoCo if you bought all the Radio Shack hardware you
> needed. Just plug the multi-pak into the CoCo, then plug in a disk
> controller and serial port, etc.
>
> I ran OS-9 on my CoCo for many years. It was the first multiuser system I
> owned, and I learnt a heck of a lot from it. And it cost me a lot less
> than any PC clone at the time.
>
> >
> > With the COCO, you're better off starting from a wirewrap panel and a
bucket
> > of parts, since the video on the COCO is not "up to snuff," i.e. 80x24
> > characters-capable. It uses that ridiculous 6847, IIRC, and even at 32
>
> To be honest, I'd rather use OS-9 on a 6809 from a teletype than (say)
> MS-DOS on an 8088 and a 80*24 video display. Video performance is not
> something I care too much about on a _computer. In any case firstly you
> could use an exernal video terminal with the CoCo under OS-9, And
> secondly the CoCo 3 has an 80*25 text mode.
>
> -tony
>
>
Received on Wed Apr 24 2002 - 22:28:07 BST