CGA Modes (Wuz: Win 3.0)

From: <(>
Date: Tue Feb 3 11:22:55 1998

I forget who wrote half of this, but here goes:

> Isn't PGA Pin-Grid-Array? (It's probably wrong, but hay....)


> You sure this isn't PGA?

PGA = Professional Graphics Adapter, as Kip Crosby so rightly pointed
out. When I was at IBM this was called PGC (C = Controller).

FWIW, the PGC was three circuit boards bolted together, the two outer
ones going into adjacent slots of an XT motherboard. It had an 8088 as
graphics coprocessor, and did 640 x 480 x loads of colours.

But back to the original question,

> I'm sure my 3270pc handles a "better" quality CGA. It just looks like
> EGA, thought it was... It was running a version of Norton Utes and it
> was just beautiful turquoise blue set and clear characters.
> I'd have to think this was better than CGA, especially since it took two
> coupled long cards to run the video...
> -Mike

No, it isn't PGA. (Although most of the chips on the cards are likely
to be PGAs, in IBM custom metal cans, as I recall...)

The IBM 5272, the 3270PC display, was a very nice monitor. I don't know
the pixel resolution, but I'd guess at 800 x 400. Unfortunately, AFAIK,
it only did 8 colours.

The 3270PC display card did TEXT MODES ONLY - it was aimed at emulating
the 3279 terminal. You could buy two add-on cards for it that went in
the slots either side in the motherboard.

1. The PS card. This provided emulation of the Programmed Symbols
option on the 3279. Very nice graphics, but only as a terminal, not as
a PC (although presumably you could have written PC drivers for it...)

2. The APA card. This provided support of the All Points Addressable
modes of the CGA. These CGA modes were displayed in the top lefthand
corner of the screen. And the only 8 colours reduced the capability
somewhat as well.

It looked very good, but AFAIK IBM never supported it properly. Pity.

Later IBM released the 5370 series machines. These included the
3270PC/G and the 3270PC/GX. These had full graphics capability, the G
on a monitor the same size as the 5272 (but with I think more colours);
the GX had a graphics coprocessor (5378) in a box the size of a PS/2
model 30 and a 19 inch monitor (5379) with lots of pixels (1280 x 1024 I
think, but could have been only 1024 x 768) and I don't know how many
colours (but might have been 64).

But your description of the 3270PC sounds like you've got only one of PS
and APA, alas.

Hope this helps

Received on Tue Feb 03 1998 - 11:22:55 GMT

This archive was generated by hypermail 2.3.0 : Fri Oct 10 2014 - 23:30:52 BST