Subject: Re: Turbochannel Card Info
To: Vance Dereksen <>
From: Chris Tribo <>
List: port-pmax
Date: 05/12/2001 09:52:55
On Sat, 12 May 2001, Vance Dereksen wrote:

> I still want the relative speed.  Just because a PMAGD-BA doesn't boot
> under NetBSD doesn't mean it isn't fast.  Just because a PMAGB-BA doesn't
> accelerate under NetBSD, it doesn't mean that it can't accelerate at all.  
> I need useful information regarding the hardware's capabilities.  Come on.

	Oh you want information regarding the hardware's capabilities? Try
doing a search for PixelStamp on the web using 18 different search engines
and tell me what you come up with. Zip, zilch, nada. There isn't a single
shred of documentation released on anything relating to PixelStamp, and
seeing how it was desigined in the 1980's it's a little hard to come
by. Surely you don't think DEC actually published performance specs on
these cards do you? The classified all information regarding
PixelStamp as company confidential, and was never released, only
snipets of the Xserver source were ever seen by the public AFAIK. What
kind of hardware capability information do you want? Let me do a little
rundown of the information on the model support page + a little more.

PMAG[A]-A mfb Dumb linear mono FB
PMAG[A]-B cfb Dumb linear color FB
PMAG[A]-C PX Lo-end PixelStamp with an eye toward some 2D and 3D
	acceleration, but not much on the 3D side. Has either two or 4MB
	of RAM, I think.
PMAG[A]-D PXG Mid-range 8-plane PixelStamp 3D accelerator with optional
	hardware Z-Buffer RAM, has three rendering engines(?) including
	an onboard Intel i860 @ 44MHz for command packet decoding and
	hardware cliping / transforms / drawing. It has three RAMDACs, one
	for each color. Full triangulation design, whatever that means.
PMAG[A]-E PXG+ same as above, only 24 plane instead of 8 plane.
PMAG[A]-F PXG+Turbo same as above only *96 PLANE* I think it has four
	rendering engies, counting the i860 running at 60MHz (?)
PMAG[A]-J 8/24 plane non-accelerated linear fb.
PMAGB-B HX/sfb 2MB VRAM, 2D accelerated linear fb. Designed specifically
	for fast scrolling in X and at the console. Has 64x64 hardware
	cursor. I belive it has something nearly like a BitBLT, though I
	don't know much else about it its internals.
PMAGB-J TX Same or close to PMAG-J, think this also has the option for
	audio and video capture, though I don't know anyone who has 
	purchased the software from DEC to do it.
PMAGC-A PV ZLX/M1 PixelVision 3D accelerator, improved on PixelStamp
	design. Don't know anything else about it.
PMAGC-B PV ZLX/M2 Same as above only with Z-buffer I think
PMAGC-E PV ZLX/L2 No idea, they call it thePVLite-MID
PMAGD-A ZLX/E1 HX+ (sfb+ like improved PMAGB-B) and 8 plane PixelVision 3d
PMAGD-B ZLX/E2 HX+ and 24 plane PixelVision 3D without Z-Buffer
PMAGD-C ZLX/E3 HX+ and 24 plane PixelVision 3d with Z-Buffer

	I don't know anything more about PixelVision because I don't own
one, but I'm sure it's better / faster than PixelStamp.

	It should also be noted that there are several different FirmWare
revisions for the PX/PXG cards, as well as the PMAGB-B's. Later firmware
revisions will likely give you better performance. The hitch: there is no
available TurboChannel flasher for pmax, there is a flasher for Alpha
3000's, but I don't have any further information about it. Without an
Alpha console to flash it from, you'd have to pull the EEPROM on a
PX/PXG. I think the PMAGB-B's is soldered on, so you have to flash it. The
Alpha people would probably know more about that than I would.

> The 5800 is XMI/VAXBI with MIPS CPUsets.

	If you had pictures you could probably ask someone on the VAX port
to identify some of the hardware in the machine, but my guess is that
they've never seen anything like it either. I don't even know if they are
R2x00, R3x00, or R4x00.