zippysticks
Veteran Member
I have a panel - will try and get some pictures for you this weekend.
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Ti-990
- Thread starter Caldwelltech
- Start date
Jim Hearne
Experienced Member
Thank you very much, hopefully there is a silkscreen on the rear of the PCB
zippysticks
Veteran Member
No silkscreen on the rear of the PCB, and this is the best shot I can shot without dismantling the PCB from the front panel. reluctant as I don't want to have to faff about aliging all the LED's and switches back up.
Jim Hearne
Experienced Member
Thank you very much, that should do, since i have the schematic hopefully i can trace the tracks from the LED's back to the shift registers on the picture.
I only need to be able to trace a couple to confirm the led order.
I wouldn't expect you to take the PCB off.
Thanks again,
Jim
I only need to be able to trace a couple to confirm the led order.
I wouldn't expect you to take the PCB off.
Thanks again,
Jim
zippysticks
Veteran Member
Let me know of you need anything else. I'm preparing to power this baby up tomorrow - at least for some large PSU cap forming for a few days.
A previous owner had cut off all the mains power cables and removed fuses - I'm hoping it was just a precaution before offloading the machine rather than a sign of something more sinister.
A previous owner had cut off all the mains power cables and removed fuses - I'm hoping it was just a precaution before offloading the machine rather than a sign of something more sinister.
Jim Hearne
Experienced Member
Thank you, I have been able to follow enough tracks on the picture to confirm what i needed to know.
Despite the LED's being labelled (left to right) as Bit 8 to Bit 15 and then Bit 0 to Bit 7, that is the correct order.
Funny how they used 4 x 5 keypads (only using 2 rows) for the switches, i wonder if they were they same as there calculators.
Good luck with your power up.
Jim
Despite the LED's being labelled (left to right) as Bit 8 to Bit 15 and then Bit 0 to Bit 7, that is the correct order.
Funny how they used 4 x 5 keypads (only using 2 rows) for the switches, i wonder if they were they same as there calculators.
Good luck with your power up.
Jim
Jim Hearne
Experienced Member
Here is my recreation of the programmers panel for use with the 990/10A pcbs.
It's not intended to be an exact copy, it's smaller and i have used SMT caps and resistors. But the circuit is 100% the same.
Just ordered some boards.
It's not intended to be an exact copy, it's smaller and i have used SMT caps and resistors. But the circuit is 100% the same.
Just ordered some boards.
zippysticks
Veteran Member
Very nice - let us know how you get on.
Made some progress with my system at the weekend. I have managed to rewire the entire AC mains supply and it is now working - at least beyond the huge 240v->115v mains transformer, filters and to the AC power conversion board. Hope to get more time this weekend to get into the DC. Three 115V fans in the chassis are incredibly loud.
Made some progress with my system at the weekend. I have managed to rewire the entire AC mains supply and it is now working - at least beyond the huge 240v->115v mains transformer, filters and to the AC power conversion board. Hope to get more time this weekend to get into the DC. Three 115V fans in the chassis are incredibly loud.
FarmerPotato
Member
I am curious how you will go about capturing these images?
I discovered 8" floppies among my dad's papers. They contain backups of DX10 user directories.
I now have an SA850 floppy that needs power and interface. I hope to connect it to Kryoflux to get track images. The rest is software...
Martin Hepperle
Experienced Member
- Joined
- Nov 10, 2014
- Messages
- 226
That was easy ... I sent the floppy disks to a friend who has an 8" disk drive and appropriate software.
This is still work in progress and I can report back in a week or so.
A Kryoflux or similar device sounds also very suitable for this purpose. The format seems to be IBM standard.
This is still work in progress and I can report back in a week or so.
A Kryoflux or similar device sounds also very suitable for this purpose. The format seems to be IBM standard.
Martin Hepperle
Experienced Member
- Joined
- Nov 10, 2014
- Messages
- 226
Christian has created image files of the floppies and placed them on their FTP server at the computer museum in Stuttgart, Gemany.
ftp://computermuseum.informatik.uni-stuttgart.de/ti/990
The files might find their way to the official bitsavers archive.
ftp://computermuseum.informatik.uni-stuttgart.de/ti/990
The files might find their way to the official bitsavers archive.
Doh. Now I remember you posting this elsewhere. I think. Sorry I missed your request earlier, here, for photos of the original.
I see they made it to bitsavers, too. Thanks, Martin!, Thanks, Christian!
The schematics for the logic board of the display are online in the manual. Shouldn't be too hard to duplicate/modify for use with most any CRT. http://www.bitsavers.org/pdf/ti/terminal/crt/0945424-9701_911_Depot_Maintenance_Manual_197902.pdf.
Apparently there is more than one version of the keyboard, using different makes of switches. You'd have to open it up and look. I've never opened up the ones I'm supposed to have, but Cape Girardeau dude on Ebay has a picked-over 911 kbd he say is Hi-Tek/Stackpole.
Bright side, you do have both an asynch and a synchronous serial port on the CPU board. The former can be used to attach an RS-232 terminal.
Last edited:
acorn_1401
Experienced Member
Were you able to power this up ok?
zippysticks
Veteran Member
No - AC supplies all ok but I think the clock generator on the power supply has failed. Not had any more time to investigate that yet. Will look again at Easter.
commodorejohn
Veteran Member
Here's hoping to hear that it is risen indeed
Jim Hearne
Experienced Member
Here is the real version of my programmers panel.
A couple of issues on the Issue 1 board, should be correct on the Issue 2 schematic which i've attached.
The circuit is an exact copy of the TI panel but it's laid out to no specific size as as the time i didn't have a chassis it needed to match.
Jim
A couple of issues on the Issue 1 board, should be correct on the Issue 2 schematic which i've attached.
The circuit is an exact copy of the TI panel but it's laid out to no specific size as as the time i didn't have a chassis it needed to match.
Jim
Attachments
zippysticks
Veteran Member
That looks fantastic Jim.
By the way, with the plastic surround, my original panels bolt directly onto a standard 19" chassis
By the way, with the plastic surround, my original panels bolt directly onto a standard 19" chassis
Jim Hearne
Experienced Member
Thank you
I've now got a card cage / motherboard but it's not a genuine TI one, came from Richard Norman like my 990/10A card and is a bit narrower than 19"
I've now acquired a 990/5 processor card, a couple of TFDC cards, a 911 VDU card and a GPIB card so having fun going through them.
Does anybody know about connecting a gotek up to a TFDC card instead of a 8" drive ?
Jim