Re: The Apple ][ was cool!

[Roy Miller <millers@inebraska.com>]

Leonard Erickson wrote:

> Roy Miller wrote:
> >
> > william strutts wrote:
> >
> > > EMM memory was developed because the
> > > 8088/8086 used a 20 bit address bus that limited the memory to 1 meg.
> >
> > No. EMM only works with the 80206 or higher CPUs.
>
> Very much incorrect. The EMM *driver* requirtes a *386* or better. The
> LIM/EMS standard required special hardware which EMM *emulates* on a
> 386.

EMM, as I recall, worked with 286 based PS/2s. Granted, it's old memory, and derived
from MANY rereadings of DRI's DR-DOS 6.0 manual.

>
>
> I have an old XT in the other room that has a 2 meg Intel Aboveboard in
> it. It supported LIM/EMS. And with the EMM driver for that board and a
> copy of QRAM (the XT equivalent of QEMM) I was able to create UMBs, load
> drivers into upper memory, etc.

Did the Aboveboard have a 286? EMM DID stand for Extended Memory Manager, didn't it?
And it takes a 286 or higher to have the extended memory, or so I thought. As
opposed to Expanded Memory Manager.

>
>
> And because the XT *doesn't* require reserving the E000 page the way the
> AT does, I was able to get 64k more upper memory than with the AT I
> later had the board it.
>
> In fact, between QRAM and 4dos, I had more than 630k of lower memory to
> load applications in. All my drivers, TSRs, etc as well as the
> non-transient portion of 4dos loaded into upper memory. And I had an 80k
> EMS sawp space and a 1 meg RAM disk.
> Since the system was also running at 10 MHz, and using a V20, it was
> quite an "XT".

I also had a 10 mhz V30 based machine with 2 megs of EMS 4.0 (software, it was 3.2
hardware - oh the pain, the pain!), and since I used WordPerfect Library/Office with
WP, PlanPerfect and DataPerfect, I had a full office suite that I loaded only one a
day and task switched in a blink! I loved that system, and did mountains of work
with it.

>
>
> > > Considering that the architecture of the PC was based on the 8-bit
> > > processor with a 20 bit address path, it was logical that IBM would
> > > utilize an OS that had was limited to that much memory.
> >
> > Huh? The 8088 was a 16 bit CPU, with an 8 bit data bus, and a 20 bit address
> > bus.
>
> Until IBM redefined the term in their publicity, having an 8-bit data
> bus made the 8088 an 8-bit cpu. Really. You'll find articles in the
> computer magazines at the time raking IBM over the coals for lying about
> it.

Guess I don't go that far back. Though some of my unread Bytes do....

>
>
> The 8086 was a true 16-bit cpu by the old definition. The 8088 got used
> instead because 8-bit parts were cheaper. Which made the motherboard
> cheaper as they only needed 8-bit buffers and the like.
>
> > The 8086 is a 16 bit CPU with a 16 bit data bus, and a 20 bit address bus.
> > Neither was an 8 bit CPU. An 8 bit CPUs have (normally) 16 bit address lines.
>
> See above.
>
> > 1986. And for word processing, or for spreadsheet work, the PC was faster. Why?
> > It didn't have to spend so many clock cycles supporting a graphical display. It
> > spent it's time doing work
>
> Yeah, it's instructive to compare a text only display and a graphical
> one. The old HGC+ screamed in Worperfect *and* supported more text mode
> fonts than VGA does even now.

I always wanted the Herc RAMFont card. Fast, with different fonts on the screen! And
GEM didn't look too bad in mono, GEOS was a bit different though.

Roy

>
>
> > Some Wintels still have an ISA or two - usually for modems. But I agree, the
> > ISA 8 and 16 bit is about as dead as EISA. Though not as dead as Micro-channel!
>
> I'm still using some microchannel and EISA systems. They work just fine
> for what they are doing, and the hardware was paid for a long time ago.
>
> BTW, you forgot VLB. <g>
>
> --
> Leonard Erickson (aka shadow{G})
>  shadow@krypton.rain.com        <--preferred
> leonard@qiclab.scn.rain.com     <--last resort