Chris Tribo <t1345@hopi.dtcc.edu> wrote

Digital has never included A designation in TURBOchannel framebuffer
option card identitication string "PMAG". 

> PMAG[A]-A mfb Dumb linear mono FB
> ...

They followd a rule to add B, C, ... when it's a revised, remodeled or
higher-grade version.

NetBSD has accelerated PMAGB-B driver for long time.  The driver has
been developed on my Personal DECstation.  Unfortunately, it's not
enabled in NetBSD/pmax due to some technical difficulties in
keyboard/mouse support.

> The PMAGD-BA is called the ZLX-E2 which is a PMAGB-B bundled with
> a PixelVision 3D accelerator with no hardware ZBuffer all on one
> card.

PMAGD has a variation across 8bpp only, 24bpp capble and plus Z-buffer
gismo.  It's designed around SFBplus graphics ASIC.  Though it's
capable of doing higher performance image copy in limited
circumstances, it's par with its ancestor PMAGB.

> PMAGB-B HX/sfb 2MB VRAM, 2D accelerated linear fb. Designed specifically
>       for fast scrolling in X and at the console.

Design of SFB ASIC is well described in Digital Western Research Lab's
paper.  I wrote dev/tc/sfb.c code by using it.

Tohru Nishimura