TI-99/4A manuals and documentation project

[CC Clarke]

I've used Visio professionally for fifteen years to create schematics. There are lots of programs to create them, as well as simultaneously building PCBs or logic testing circuits as they're designed, but for all-around ease of use and interchange between Word and PowerPoint, Visio is hard to beat when all that's required is a schematic.

 

I once worked in a place as a consultant where the principle engineers were delivering schematics in different formats. It looked like multiple companies were designing the electronics on the same floor. As the end user, I sat everyone down and told them we weren't leaving the room until we standardized the documentation. Every drawing had a different look and it was driving me nuts.

 

Based on my recommendation, (I wasn't a Visio user then) Viso beat AutoCAD -which was used by one guy who had been around forever and wasn't about to change "his way". AutoCAD was total overkill for a 2D environment - trying to get revisions out of him was like pulling teeth. The AutoCAD designer went ape$h!t and walked out the door that day. He was as hooked on complexity as I was on simplicity. After that, all of our docs had a common "look" to them and once I subsequently learned Visio, was able to make changes on the spot.

 

TI has a common look to their documentation, which make learning the circuity and troubleshooting much easier. Most large companies have a standardized format designers and tech writers are required to adhere to. Visio can't do everything, but there are circumstances where it works very well and is affordable for the average home user. Best of all, it's very easy to learn with a workflow that has commonality with other Microsoft apps.

 

CC

Edited December 25, 2016 by CC Clarke

[+Ksarul]

I've been doing some more documentation work. I've also corrected a few errors and omissions on some of the earlier schematics, so this set is the one you want to keep.

A3-FORTI-P1.pdf

A3-IEEE-488-P1b.pdf

A3-IEEE-488-P2b.pdf

A3-PEB-Speech-P1(R2a).pdf

A3-SAMS-P1(R5a).pdf

A3-SAMS-P1(R6c).pdf

A3-SAMS-P2(R6c).pdf

[+jedimatt42]

Looking at the speech-peb board, it seems you could feed sbe into the 555 using the output from U8 so the led won't activate if ama/b/c are in the wrong state.

 

-M@

[+Ksarul]

I have also been playing around with the PEB circuit card templates Sinphaltimus did a while back. Here is a set including labels for eight different TI PEB cards. . .and the blank template label. Note that amperage levels vary quite a bit between cards and there is a lot of additional text on the p-Code label. I hope someone finds use for these. I have some being made up as vinyl labels, but at two to a sheet each label costs about $3, so that's not too cost effective. Printed ones on some high-quality paper that gets laminated afterwards would probably work out much better from a pricing standpoint. It may also last longer in a PEB based on heat load. . .

[+Ksarul]

I thought of moving the position of the SBE signal sense for the LED to the U8 output as you suggested Matt (while I was doing the original layout), but that part of the board was pretty tight when it came to trace space, so I moved it to where it is now as a compromise. You shouldn't see the AMA, AMB, and AMC signals as anything but high in most regular PEBs There will be some change with a SNUG SGCPU in there or with a Geneve (the only two boards I've seen that actually use these signals). With where it is now, sound output will be inhibited by AMA/B/C, but the LED will still flash if something tries to access the card. I looked at it as a possible troubleshooting aide--a flash without sound could identify a problem in the AMA/B/C lines on anything but a Geneve or SGCPU.

[+Ksarul]

Here are some more schematics, this time for the TI Video Controller card and its relay box. There is a bit of uncertain data at the middle of page two (identified as such). I also used the same design schema that I've used with the other schematics, so this one looks quite a bit different at times from the fuzzy TI copies I have access to, but it misses none of the details (and it is a lot easier to read).

A3-Video Controller Card-P1.pdf

A3-Video Controller Card-P2.pdf

A3-Video Controller Card-P3.pdf

A3-Video Controller Card-P4.pdf

A3-Video Controller Relay Box-P1.pdf

[kl99]

Here are some more schematics, this time for the TI Video Controller card and its relay box. There is a bit of uncertain data at the middle of page two (identified as such). I also used the same design schema that I've used with the other schematics, so this one looks quite a bit different at times from the fuzzy TI copies I have access to, but it misses none of the details (and it is a lot easier to read).

 

Hi Ksarul, I don't have the schmematics but the actual card. Can it be used to help out removing uncertainty?

http://www.ti99.eu/?page_id=1223&lang=en

[+Ksarul]

kl99, I went through your pictures carefully and was able to answer the remaining questions I'll upload an update to page 2 once I finish making the updates to my master file. . .many, many thanks! Vielen, vielen Dank!

[+Ksarul]

I still have to modify my master file for the Video Controller, but I did do some other weird work this week. I found a series of drawings that assembled together to make a schematic for the Mechatronic 80-Column Card, so I turned them into a nice set of schematics. Here they are, for those of you who need them. The second page is just the cable and some of the connectors, but they were an integral part of the original schematics, so I included them here too.

A3-Mechatronic 80-Column Card-P1.pdf

A3-Mechatronic 80-Column Card-P2.pdf

Edited February 6, 2017 by Ksarul

[fabrice montupet]

Thank you! :-)

[fabrizio]

many thanks !

[+Ksarul]

I had some time to play with schematics again, so here are the schematics for two more PEB cards: the Myarc FDC with some mods by Michael Becker and the Australian Quest 200 RAM Disk.

 

 

A3-Myarc FDCC-1 Disk Controller Card-P1(R2a).pdf

A3-Quest 200 RAM Disk-P1.pdf

A3-Quest 200 RAM Disk-P2.pdf

[+mizapf]

Very good, Jim! Every such schematic is the most valuable piece of information for emulating a card in MAME. Do you also have Corcomp Disk controller schematics?

[+Ksarul]

I built that schematic from scratch, Michael, using a Myarc FDC that I completely disassembled, several photos of the modifications Michael Becker did to one of the boards from Richard Bell, and a CAD file that I've been building to try and replicate the boards. I still need a copy of the PAL code Michael Becker used on this board to do that, as the PAL is locked. Are you in contact with him at all? It is possible Harald Glaab has the code as well. It would be good if code for all of his PALs were available somewhere, as that would ensure that those of us on this side of the ocean could actually repair boards with PAL problems.

[+mizapf]

Have a look at your mailbox.

[+Ksarul]

Many, many thanks, Michael! You really made my week!

[+mizapf]

It should be stressed that Michael Becker and the SNUG people deserve the credit for reading out the PAL; I guess they did it by exhaustive testing, which is pretty well feasible as long as the PAL is not registered.

[+Ksarul]

Agreed! It is a real pain to read out a locked PAL--it takes a lot of patience and experimentation to make sure you have everything right. I am really glad Michael Becker took the time to do that with this one.

[+Vorticon]

I assume it's reasonable to expect a couple of new products to come out of this? Just to be safe, please put me on the list from now!

[RickyDean]

Yes me too. also, it looks like I'll be trying to figure out both the CC disk controller card and the MES, as I've pretty much replace all the logic chips in both to no avail. Oh, well, I've been doing some research on GAL and PAL readers and what it would take to understand the logic the PAL's are replacing. I believe the pics i posted about the three different RS232 cards from CC is a good starting place.

[+Ksarul]

Here is a nice crisp copy of the schematic for the BwG disk controller. . .

A3-BwG-FDC-P1.pdf

A3-BwG-FDC-P2.pdf

[+Ksarul]

One note on these diagrams--the last two digits are the page number, so if it has an associated P2, you generally need both the P1 and the P2 (or in one case the P3 and the P4 as well) in order to have the whole schematic for that card.

[+InsaneMultitasker]

I had some time to play with schematics again, so here are the schematics for two more PEB cards: the Myarc FDC with some mods by Michael Becker and the Australian Quest 200 RAM Disk.

 

 

I somehow missed this thread - very nice work! One suggestion for the controller schematics would be to label the connector pins with their respective signals. If used for troubleshooting, it is nice to have that information labeled at the connector (i.e., J1) and at the chip IO pins. I'll print the Myarc FDC schematic and see if I have anything in my notes that you might find worth incorporating. Will be nice to get rid of my partial, hand-drawn papers.

[+Ksarul]

It is possible you will find a lot you would like to see in there, @insaneone. The version here has a lot of mods done to it--I still have to go back and iteratively remove the mods to return it to the state of the earlier versions. . .I'm glad you like these. I still have a lot of PEB cards to document.

[RickyDean]

I scanned in a schematic of the Percom disk controller board, and I am currently cleaning up the scan to get rid of old paper look. Is there an interest in this being posted? Is this already on Whtech? Also I have a schematic for a FLUG DSDD card that uses a u795, I believe chip, does anyone have any information on this card? Thanks.

 

PS. Find the uncleaned version and my partially cleaned version below.

Percom1.bmp

Edited October 2, 2017 by RickyDean