TI 59 Diagnostic Card Listing

[voltaage]

Hello.

Although this is a matter not quite related to HP Calculators, I think its importance trascends to a point of document preservation.

I have a Texas Instruments Programmable 59 which has the mysterious diagnostic program written on a magentic card. I accidentally erased this program while I was trying to record another one on a faulty device. The repair process was rather though and unsuccessful, hence that I got another working machine. This one read a couple of cards I wrote on the faulty one (some minutes before it died), in which there was this diagnostic program. I realized later about what I've done because side 1 reads nothing, while side 2 reads the "77" program step test successfully.

I have not found any listing of this program on the web whatsoever. I know there there is a recent thread that explains in great detail what this test does; yet that's the only reference to this.

I would be very greatful if anyone here knows where to get a listing to this, or someone can share one of his.

Thank you.

[Ren]

(01-31-2022 09:18 PM)voltaage Wrote:  Hello.

Although this is a matter not quite related to HP Calculators, I think its importance trascends to a point of document preservation.

[...]
Thank you.

Your question is cromulent in this forum.
Though I do not have an answer for it.

[Massimo Gnerucci]

(02-01-2022 07:45 PM)Ren Wrote:  

(01-31-2022 09:18 PM)voltaage Wrote:  Hello.

Although this is a matter not quite related to HP Calculators, I think its importance trascends to a point of document preservation.

[...]
Thank you.

Your question is cromulent in this forum.
Though I do not have an answer for it.

[Csaba Tizedes]

(01-31-2022 09:18 PM)voltaage Wrote:  Hello.

I would be very greatful if anyone here knows where to get a listing to this, or someone can share one of his.

Thank you.

just for you:

[voltaage]

(02-02-2022 08:09 AM)Csaba Tizedes Wrote:  

(01-31-2022 09:18 PM)voltaage Wrote:  Hello.

I would be very greatful if anyone here knows where to get a listing to this, or someone can share one of his.

Thank you.

just for you:

Intense listing, my calculator appreciated.

[Csaba Tizedes]

(02-02-2022 06:46 PM)voltaage Wrote:  Intense listing, my calculator appreciated.

Yeah, the YouTube sent a warning because of the background music copyright issues...

[Tinue]

Maybe you can reconstruct the code from the magnetic pattern:



The lower part is the actual diagnostic routine, and the upper part seems to be an even less documented test pattern to stress the card reader.

[voltaage]

(02-03-2022 05:58 PM)Tinue Wrote:  The lower part is the actual diagnostic routine, and the upper part seems to be an even less documented test pattern to stress the card reader.

That picture is a beauty to look at! At some point, I wondered about buying one of those magnetic tape viewers to inspect cassettes and credit cards. I coudn't hold my curiosity of taking my magic electromagnetic signal detector (which is just the guts of a walkman packed in a thick pen aseembly with a speaker) to hear what was being recorded on the card. Just a wooey mess good for fun beats.

The second side clearly reveals the "77" step test, in its four track glory.

Did you use ferrofluid to take the picture?

[Tinue]

(02-03-2022 08:52 PM)voltaage Wrote:  Did you use ferrofluid to take the picture?

Yes, I did. A few years ago I had the idea to possibly read out these magnetic cards optically, and do some sort of OCR to retrieve the data. As the picture shows, the resolution that can be achieved with ferrofluid is not good enough. The picture is the best one of many attempts, by the way.

I somewhat successfully restored the card reader of a TI-59, but it still only writes and reads back successfully maybe one in five cards. As for reading my old cards, the success rate is almost zero.

Maybe a better attempt would be to read the amplified raw magnetic flux data right at the op amp with an Arduino and try to recreate the bits this way, but in the end it's probably not worth the effort.

(02-03-2022 08:52 PM)voltaage Wrote:  The second side clearly reveals the "77" step test, in its four track glory.

Right, I forgot: This is mentioned in the manual. Steps 240-479 all contain code "77".

[Tinue]

I decided to have a bit of fun, and played with the only hardware TI 59 emulator that I know (TI-59E)

Diagnostic runs fine, and I attached the listing and three files here. The files are:

• diag.pdf: The listing
• diag-1.c59: Page 1 of the magnet stripe
• diag-2.c59: Page 2 of the magnet stripe
• diag.m59: Full memory snapshot after loading both pages
  

[voltaage]

Hello Tinue.

Have you tried disassembling the mechanism to clean the heads? Probably the pressure pads are worn out or gummed up in dirt. Also, be careful if your roller is starting to deteriorate; it may destroy your cards.

[Tinue]

I had to perform a full restore, including a new roller and pressure pads. The old roller was dissolved all over the mechanism and quite hard to clean out.

I made a few tests, and it appears that many of the blank cards have deteriorated. When I write the "77" pattern and read it back, there are quite some errors even if the display does not blink after the read step. About half of the cards work fine though, so I guess the reader is ok.

The cards that I have written in the early 80ies are impossible to read, they all show an error after the card ran through the reader. I tried to make the reader faster and slower with the pot, but none of the settings worked.

[Sylvain Cote]

To cleanup my magnetic cards used in HP calculators (65/67/97/41/71/75), I use a:

1) Staedtler Mars Plastic Premium Eraser to remove the oxidation on the magnetic side, then
2) rub the same side with isopropyl 99.9% alcool

Most of the time (90+%) the card is working perfectly after the cleanup.

You have to be very careful to not pinch the card while using the eraser.
After pinching some cards, I have build a cleanup-jig to prevent that and I have not lost any card since then.

Sylvain

[voltaage]

(02-08-2022 09:22 PM)Tinue Wrote:  The old roller was dissolved all over the mechanism and quite hard to clean out.

Yeah that is quite disgusting. I'm glad you found a roller that could fit the shaft.

(02-08-2022 09:22 PM)Tinue Wrote:  I made a few tests, and it appears that many of the blank cards have deteriorated.

The cards that I have written in the early 80ies are impossible to read, they all show an error after the card ran through the reader. I tried to make the reader faster and slower with the pot, but none of the settings worked.

I would not file this as a defeat yet. When I got my second 59, it had a card in the slot which had seen better days. The pencil labeling was smeared, almost unreadable, and the magnetic side had clear marks of where the head and the rollers had been. Even with that much dirt, it still read without errors

Alas, the program written was not very useful for me, so I decided to thoroughly wipe down the card. I thought (since it is pencil after all) to use a natural eraser to clean the label part of it. Although I could easily get the letters off, it left a sticky matte finish on the card; not to mention that it smeared a bit the Texas Instruments logo and degraded the yellow color (probably time had already pre-done the job on the color). It seemed unfixable, but a dry cotton cloth helped me out by removing that layer, revealing the true shiny and glossy coating of the card (like transparency film).

As for the magnetic side, just picking a cotton swab soaked with isopropyl alcohol revealed that the ferrose compound which had some small deterioration. Not that significant fortunately. After all it gave that other side the same shiny look as the label, not the original matte look as in 5.25" diskettes.

If all of that doesn't work, then you have two options: the card is bad and unfixable, or as it happened in my experience that, you should write that card many, many times in order to get the magnetic particles moving again.

(02-08-2022 09:51 PM)Sylvain Cote Wrote:  To cleanup my magnetic cards used in HP calculators (65/67/97/41/71/75), I use a:

1) Staedtler Mars Plastic Premium Eraser to remove the oxidation

Yeah I agree. Plastic Erasers would have avoided the stickiness of bread.

[Dave Britten]

(02-09-2022 02:05 AM)voltaage Wrote:  

(02-08-2022 09:51 PM)Sylvain Cote Wrote:  To cleanup my magnetic cards used in HP calculators (65/67/97/41/71/75), I use a:

1) Staedtler Mars Plastic Premium Eraser to remove the oxidation

Yeah I agree. Plastic Erasers would have avoided the stickiness of bread.

I use one of the white Pentel Hi-Polymer erasers - which looks to be about the same as the Staedtler - with good results. Generally you won't be able to recover the data on a card that has become unreadable, since cleaning the card with the eraser likely destroys the recorded data further, but it works wonders for deoxidizing the card and making it usable again.

These cards generally seem to hold up well over time as long as they've been recorded from a good machine and the cards aren't already oxidized when recording. I bought a pack of 40 or so used TI-59 cards that contained all the programs from the EE module, and I think all but one side of one card still read just fine on the first try. I'm assuming these were written back in the '80s.

[Sylvain Cote]

(02-09-2022 02:14 PM)Dave Britten Wrote:  Generally you won't be able to recover the data on a card that has become unreadable, since cleaning the card with the eraser likely destroys the recorded data further, but it works wonders for deoxidizing the card and making it usable again.

This is not my experience with HP cards/readers, most of the time I am able to recover my data after cleaning oxidized cards.

[Dave Britten]

(02-09-2022 08:15 PM)Sylvain Cote Wrote:  

(02-09-2022 02:14 PM)Dave Britten Wrote:  Generally you won't be able to recover the data on a card that has become unreadable, since cleaning the card with the eraser likely destroys the recorded data further, but it works wonders for deoxidizing the card and making it usable again.

This is not my experience with HP cards/readers, most of the time I am able to recover my data after cleaning oxidized cards.

Interesting! I haven't had luck in that regard, but good to know it's more possible than I had realized.