Hello All,
I've seen references to a CP/M port for the IBM Displaywriter in magazines of the era. Has anyone ever seen this beast in real life? Better yet anyone have a copy of it?
> From: Don North
> If the bootstrap card is an M9312 with the standard console PROM, it
> does NOT require any memory to be present/accessible to get to the ODT
> prompt that prints out the registers and waits for a command.
Ah, right you are; I'm not familiar with the M9312 codes (you seem to have
that all well in hand :-), I've only studied the M873 and M9301 codes.
But the M9301 'console without testing' code does in fact look like it would
run without any memory in the machine. (Which explains some odd features in
the code - I'd always wondered about the 'unusual' subroutine caling
sequence, but now I see it allows it to work without any memory.)
> From: Ed Groenenberg
> ISTR that there is a jumper which selects for +12 or +15 volt.
Not that I am aware of - see the power circuitry in the drawings, MP-00742,
pg. 25. Maybe you're thinking of the M7891 (MS11-L), which does have such
a jumper?
>> The M7891 uses +/-15V as well as +5V?
> Yes, both +5 and +15 is used and measure ok on the backplane.
Actually, having looked at the prints, it also uses either -5V or -12V/-15V
(there's a jumper). So you might want to figure out i) which your system has
(in a BA11-K box, if you have an H745 'brick' you will have -15V, if an H754
-5V; if a BA11-L box, different versions of the H777 provide different
voltages, but I'm too lazy to check :-), and ii) check to make sure the -
voltage is good too.
Although I doubt the - voltage is causing this problem; I'm pretty sure only
the memory chips use it, so it's it's not right, probably the memory would
return bad data, is all.
Noel
I just became the happy new owner of a nice old HP 41C calculator with a matching barcode wand. I haven't powered it up yet, as there's lots of battery compartment corrosion. I'm looking into getting one of the replacement flex circuit assemblies that have been made for it. I was quite curious about the 41C when I saw them in magazines, but I had never touched one before. My first HP calculator was a 28S, and I finally upgraded to a 48GX a couple of years ago. I think this 41C will be a fun addition to my collection once I get the battery compartment fixed up and get it running.
If anybody has any interesting HP 41C peripherals or accessories available for trade, let's talk! eBay and I don't talk any more, so I need to find my new toys the old fashioned way.
--
Mark J. Blair, NF6X <nf6x at nf6x.net>
http://www.nf6x.net/
I bought a few cases of those not all that long ago... Let me see if I can
dig up the source.
Mike
On May 15, 2016 2:38 PM, "Mark J. Blair" <nf6x at nf6x.net> wrote:
I think I already know the answer to this ("no"), but is there any
remaining source of usable, or at least restorable, ribbons for the DEC
Correspondent printing terminal? The re-inking roller in the single ribbon
that came with my printer is hard as a rock. Maybe I'll be able to restore
the roller or fabricate a new one, but I wouldn't mind having more ribbons
on hand in any case.
--
Mark J. Blair, NF6X <nf6x at nf6x.net>
http://www.nf6x.net/
I am glad to see this effort of Jon's remain Independent. I believe he
would have wanted it that way.
Ed Sharpe archivist for SMECC
In a message dated 5/11/2016 11:50:30 P.M. US Mountain Standard Time,
curiousmarc3 at gmail.com writes:
This is great news despite the sorrow. Thank you for that, the museum is
such an awesome resource for HP collectors. I saw your video on the 2116
restoration were both Jon and you appear. We have at least one more at the
CHM, just as a static display for now. I hope I can visit you in Melbourne one
day.
Marc
Sent from my iPad
> On May 10, 2016, at 2:25 PM, Paul Berger <phb.hfx at gmail.com> wrote:
>
> The following was posted on hpmuseum.org this morning:
>
> *RE: Jon Johnston Passes *
> As an update to the sad news of Jon Johnston's death, I can advise that
the HP museum and the hpmuseum.net website he built will be continued and
maintained for the foreseeable future.
>
> Over the last 8 months I have worked with Jon in restoring items from
his collection of equipment and, among a range of items, recently restored an
HP2116A computer to working order - one of only two Jon was aware of in
the world and the only one that's operational.
>
> At this stage we have not been able to access the website and put any
notices or updates but that should be addressed shortly.
>
> Jon's wife has asked me to look after the museum and website for the
foreseeable future and as much as possible, continue to develop the museum in
line with Jon's vision and objectives.
>
> As a short background, I joined HP Australia in 1982 as a Customer
Engineer maintaining HP3000s, HP250s, all peripherals, terminals etc. I stayed
with HP for over 26 years (including 5 years in Palo Alto) in a range of
Services roles and have many fond memories of the company and the people I
worked with.
>
> While my ability to invest time into the museum is more limited than
Jon's, I hope to honour both his memory and the legacy of the 'old HP' by
keeping the museum going as best I can, hopefully with help from the HP
interest groups across the world.
>
> David Collins
>
I think I already know the answer to this ("no"), but is there any remaining source of usable, or at least restorable, ribbons for the DEC Correspondent printing terminal? The re-inking roller in the single ribbon that came with my printer is hard as a rock. Maybe I'll be able to restore the roller or fabricate a new one, but I wouldn't mind having more ribbons on hand in any case.
--
Mark J. Blair, NF6X <nf6x at nf6x.net>
http://www.nf6x.net/
I just got the new boards:
https://www.flickr.com/photos/22368471 at N04/albums/72157668325096875
Differences of new version:
* bezel is black with white legends
* legend font is a bit larger and heavier
* legends are above switches
* switch PCB wiring errors fixed
* right angle header
* plastic caps installed on all toggles
I assembled the new one with C&K switches that are more readily
available (e.g., from Digi-Key and Mouser), but I don't like them as
much. Originally I used switches with a V-bracket which makes
alignment and assembly easier, and they have a uniform threaded
bushing height. The more common toggle switches have a longer threaded
bushing. This can be seen by comparing the edge-on views; for the more
common switches without the V-bracket, the red switch body is seen.
I'm soliciting input as to whether the switch legends should be
changed from the vector font to a "real" font, and if so, what font
and size is desired.
> From: Rob Doyle
> the 'objcopy' utility in the Binutils package can translate between
> binary, tekhex, srec, ihex, etc.
Right, but the problem is that I had dumps which were what the PDP-11 CPU
saw, but due to hardware oddities on the M9301 board, the _ROM contents_ were
diferent: bits 1-8 (_not_ 0-7, which would have been simpler :-) have to be
inverted. I'm not sure any existing tool could manage that!
Speaking of hardware oddities in the M9301, it seems the Tech Manual
(EK-M9301-TM-001) has an error: it seems to indicate that the first (low)
words in the PROM should contain the first words at 173000 ("address
locations 773000 .. are located in the lower 256 words of the PROM", pg. 2-7).
However, looking at the prints, the signal "765XXX L" is fed into the high
address bit of the PROMs, and looking at how it is generated (Fig. 2-8, pg.
2-8) it should be low when the low addresses (765xxx) are being read, so the
low addresses in the PROM should correspond to 765xxx?
Also, looking at Mattis' read-out of the actual PROMs, they have the code
that's at 773000 at 0x100 in the PROM.
So it does seem as if the PROMs aren't organized the way the Tech Manual
claims...
Noel
> From: Glen Slick
>> No, but I do have a un-annotated dump in octal. Can you point me at
^^^^^
>> a description of Intel HEX format
> Or you could just use the SRecord tool package to convert between
> binary / Intel hex / Motorala hex
I had a look through the doc, but I couldn't find 'octal' anywhere... :-)
And anyway, my format is not identical to either Intel or Motorola, so I'd
have to write a converter _anyway_, to get from my format to something a tool
would understand. (Converting my dumper to emit Intel instead of my format
would still mean a lot of work, because I have all these boards dumped in my
format - I'd have to swap them all into the machine to get Intel-format dumps.)
Plus to which the M9301 ROM format is kind of wierd; the high addresses on
the bus (173000 and up) go in the low locations in the ROM, and the low
locations (165000 and up) go in the high, _and_ the low bits (0377) of each
word (i.e. the two ROMs which hold the low bits) have to be inverted because
of a kludge on the M9301 having to do with the way it writes the contents of
the switch to the bus when the machine is starting. So all in all, it's just
easier to...
>> I already have a program to read my octal dump things, so I'll just
>> have to tweak that a bit.
Which turned out to be pretty easy - probably easier (for me, at least) than
understanding the documentation on the SRecord tool page well enough to
understand how to make it do what was needed... :-)
> From: Pete Turnbull
>> Can you point me at a description of Intel HEX format
> Take a look at http://www.dunnington.info/public/IntelHEX
> There's a description and also some code you could adapt.
Thanks for that; alas, by the time I saw it, my brain had turned on and I
remembered this wonderful thing called 'Google', which had led me to info
about the format! :-)
Noel
