28 Feb
2022
28 Feb
'22
11:49 a.m.
On 2/26/2022 3:21 PM, Tony Duell via
cctalk wrote:
On Sat, Feb 26, 2022 at 5:19 PM js--- via
cctalk<cctalk at classiccmp.org> wrote:
Hi, Tony! Long time!
Thank you VERY MUCH for your very
generous offer!
Dave McGuire was extremely kind to send
me a ROM dump of the HP 9915's 8048,
that he had -- to my amazement --
already made for himself. So to my
complete surprise, I do have the ROM
contents at this point.
I've a Data I/O 2900 which supposedly
can program the 8748, so I'll give that
a try if I can figure out how to use it
again (been a long time). I've ordered
a NOS 8748 off eBay.
I'll give all this a try and post
results here.
- John Singleton
As the chances of success are highly
improbable, looks like I'm SOL on this
particular motherboard.
My bench is rather full at the moment and will be for a
few more weeks...
But if you get no other help and you can wait a bit, I believe one of
my old EPROM programmers can read the 8048/8748 with the right
adaptor, and the schematic of that is in the manual. I also have a
working (I hope) HP9915. So I could have a go at making said adaptor,
extracting the 8048 from my HP9915, and readng it out. You would then
have to find somebody who could program the ROM image into an 8748.
-tony