[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: Upgrading an Unenhanced IIe
Knut Roll-Lund wrote:
Scott Alfter wrote:
Great Hierophant wrote:
Finally, Apple must have rewired the unenhanced IIe board to allow it
to do DHGR.
Unless you have a Rev. A motherboard (which is unlikely), the board you
already have will do DHR. No modification is necessary. If you're
using an
Apple extended 80-column card (or maybe some clones), there's a jumper on
the card that should be installed to enable DHR.
Hi
I'm wondering what that jumper would be doing. Just connecting two
signals from the motherboard?
It actually just connects a signal from the motherboard to
the gating on the card.
I have two 80column/64K cards, both "clones" and none of them have a
jumper.
Many later cards dispensed with the jumper, since there were
so few rev. A main boards, and no one ran with DHGR disabled.
Also none of them have RGB output so I'm wondering if it would be easy
to make this circuit myself, to produce the RGB signals. I have been
searching the net for info on that but haven't found anything specific.
It's not simple. There are plenty of RGB add-ons for AUXRAM cards.
They all produced "digital" RGB. Apple made a 64KB one, too.
My IIe is also rev. B and unenhanced.
I'm rather new with Apple II. It was a friend who had one and I recently
bought this IIe. My old machine from back then is a Video Genie, a
TRS-80 Model I clone. (Apple II was too expensive.)
Time and relative ubiquity have certainly taken care of that
problem! ;-)
-michael
New Applesoft BASIC interface for NadaNet networking!
Home page: http://members.aol.com/MJMahon/