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PCjr prototypes and oddities
Posted: Tue Mar 03, 2020 5:34 pm
by DoctorOctal
In January I had an exhibit at the
DFW Retrocomputing Meetup of interesting and mysterious PCjr items I found at Computer Reset. There’s a
quick-and-dirty writeup with photos online.
Featured items:
I’d be grateful for any insights you might have about these things.
Re: PCjr prototypes and oddities
Posted: Fri Mar 06, 2020 10:46 am
by Brutman
All interesting. I regret that I had known Richard for years and he never mentioned he had these things; he certainly knew my interest, both as the owner of this site and as a former IBMer.
The larger keyboard answers one question - the two keyboard layouts in the diagnostics. It looks like IBM planned on offering the larger keyboard and the built-in diagnostics support two layouts.
Re: PCjr prototypes and oddities
Posted: Fri Mar 06, 2020 5:42 pm
by toddvernon
Just because it's close to my troubleshooting right now, No resistor termination pack on the disk drive?
-todd
Re: PCjr prototypes and oddities
Posted: Fri Mar 06, 2020 8:52 pm
by DoctorOctal
toddvernon wrote:Just because it's close to my troubleshooting right now, No resistor termination pack on the disk drive?
Right. I hate to say it, but lack of termination resistors is not your problem. The PCjr drives don't come with the resistors and don't need them for proper operation.
Re: PCjr prototypes and oddities
Posted: Fri Mar 06, 2020 10:02 pm
by DoctorOctal
Brutman wrote:All interesting. I regret that I had known Richard for years and he never mentioned he had these things; he certainly knew my interest, both as the owner of this site and as a former IBMer.
Maybe he didn’t remember. I found these in unmarked boxes on top of a pallet rack at the far end of the warehouse.
I’ve heard several people say that he knew where everything was, but I’m skeptical. He might have had a better idea than anybody of what he had and where, but there’s just too much stuff in too much disarray at CR for someone to have a complete mental map and inventory. There are so many
special things, even, that one could easily forget about some of them as they’re tucked out of sight for years.
Brutman wrote:The larger keyboard answers one question - the two keyboard layouts in the diagnostics. It looks like IBM planned on offering the larger keyboard and the built-in diagnostics support two layouts.
Ah, yes, I had forgotten about the full-size keyboard diagnostics. You’re probably right:
- IBM plans a full-size keyboard (but not for the initial launch) in addition to the compact one and provides for it in the ROM diagnostics.
- The compact chiclet keyboard gets panned.
- IBM changes course, dropping plans for the full-size chiclet and releasing the revised compact keyboard instead.
Re: PCjr prototypes and oddities
Posted: Sat Mar 07, 2020 3:09 pm
by alanh
All I ask is you think about some sort of escrow plan for where these things go if (and eventually when) something happens to you. I'd like to see these end up at a museum instead of someone tossing them in the bin after a few decades are up. After all, before your rescue, much of the CRW haul might have gotten tossed to an eRecycler..
Re: PCjr prototypes and oddities
Posted: Sun Mar 08, 2020 10:46 am
by Brutman
+1 ... The full extended Chiclet style keyboard is a great example of why things should not be tucked away. I've never heard of it and I worked at IBM and talked to some original employees on the project. The knowledge of it's existence could have easily been lost forever. I knew there was something goofy in the machine BIOS, but had never expected to see a fully formed version of it.
Re: PCjr prototypes and oddities
Posted: Sat Apr 11, 2020 2:44 pm
by FortMax
The full-sized keyboard being planned for release sometime after the jr itself launched is also supported by the Guide to Operations, as Test Tag K is listed as "reserved for future use"