Apple //e (white keys) motherboard revision

[KP]

Is there a way (other than, for example, trying to play a DHR game like Bad Dudes on it) to detect whether my white-keys //e is a Rev. A or Rev. B? It is enhanced, for what that is or is not worth.

[D Finnigan]

The revision letter is marked on the motherboard. Read the part number
printed to the left of the green copyright notice. Starts with 820...

--
]DF$
The New Apple II User's Guide:
https://macgui.com/newa2guide/

[Brian Patrie]

I think it's possible to upgrade a Rev A IIe to enhanced, so
enhancedness not a foolproof indicator that it's DGR,DHGR capable.

To test it: from freshly powered on, enter:

PR#3
HGR
POKE 49246,0

If it's DHGR capable, you should end up with memory garbage from auxmem
interleaved with black vertical bars from mainmem.

[Mitchell Spector]

KP <kjp...@gmail.com> wrote:

>Is there a way (other than, for example, trying to play a DHR game like Bad Dudes on it) to detect whether my white-keys //e is a Rev. A or Rev. B? It is enhanced, for what that is or is not worth.

The most fool proof method is to look at the motherboard itself.
Examine the part number at the top-center, above the card slots.

You will see 820-0064-A for the revision 'A', and 820-0064-B
for the revision 'B'. Note there was a third revision that used the
'A' label again, and that was 820-0087-A, but is functionally a 'B'
revision board. iI is notable for having a 1984 copyright date
and the Enhanced chip part numbers silked screen on the board.

Of course the motherboard used in the Platinum Apple IIe is
also functionally a revision B board. I don't know the part number
off the top of my head, but it is visibly different as there are far
fewer chips present (firmware combined into "CD" ROM, and
just a pair of 64Kx4 DRAMs. Also likely a 1986 copyright date).

I believe Apple recommended against installing the Enhanced
chipset in rev 'A' boards, but it would still work. You just would not
have the capability to use Double-Lo/Hi-Res graphics or have
the special video data signal accessible through slot-7.

Mitchell Spector