HP97 The journey begins

[twoweims]

A Christmas Message from my HP-67:

[attachment=7960]

Courtesy of new Teenix Logic Board!

[teenix]

(12-25-2019 10:14 PM)twoweims Wrote:  A Christmas Message from my HP-67:

Courtesy of new Teenix Logic Board!

Let the games begin :-)


There is a new 67 flash file available (version 3)
See the help PDF for flashing details.

http://www.teenix.org/HPF6703.hex

This has a C register auto increment modification which will save program steps when notes are used to display a long message. The C register nibbles [11] and [12] (used for note indexing) will increment by 1 and wrap around to 00 if > 99.

For example:

001 LBL A
002 0 // start at note 0
003 PSNT // pause and display note 0
004 PSNT // note 1
005 PSNT // note 2
etc

The HP65 CPU has the same feature.

I have uploaded new CCE33 and HP-97 emulators. These have the auto increment feature added.

It was complicated to do but the HP-97 emulator can now print the notes. Image below. The original microcode is still unaltered. As with the 65 and 67, the notes code just taps into its resources.

I have done a lot of preliminary work on a HP-97 CPU replacement. It is more complex than the 65 and 67 and due to the internal calculator layout, there will most likely be some soldering required. I am looking into replacing the printer driver board and incorporate a new simpler driver for it on the CPU board, but we'll see.

I know there were some issues about printing non standard characters on the real printer, causing the print heads to burn out. In theory, the actual printer should be able to print any alphanumeric character so I think these non standard codes cause the PIK to access its ROM space in an invalid way and it "gets lost" leaving the heads turned on. With a new CPU board, this shouldn't happen leaving the printer to print what ever.

I'm not sure there is any demand though, so might not be worth all the effort.

cheers

Tony

[Helix]

Do you plan to add some kind of continuous memory?
If I've correctly understood the manual, saving a program with more than 112 steps requires 16 keystrokes. If registers must be saved too, this number reaches 24 keystrokes (not counting the PRGM/RUN switch). Almost the same hassle is required after power on.

I know this mimics the behavior of magnetic cards, but I think it would be nice to have a short sequence of two or three keystrokes for example, allowing to save the entire state of the calculator in flash memory, and to recover this state after power on.

Anyway, I am impressed by the work you have done. Congratulations!

[mfleming]

(12-25-2019 11:55 PM)teenix Wrote:  I have done a lot of preliminary work on a HP-97 CPU replacement. It is more complex than the 65 and 67 and due to the internal calculator layout, there will most likely be some soldering required. I am looking into replacing the printer driver board and incorporate a new simpler driver for it on the CPU board, but we'll see.
.
.
.
I'm not sure there is any demand though, so might not be worth all the effort.

cheers

Tony

There are probably fewer HP-97s out there, which limits the audience for a replacement board. On the other hand, the benefits are the same as with the 65/67 CPU boards; a machine with a non-working card reader becomes useful again, you needn't worry about wear on cards once they are stored in flash, and there's less wear on the card reader mechanism.

I realized the last two benefits while loading up some cards this morning and getting an Error message on a few of them. I don't know if it was just a glitch or if the mechanism is going wonky on me. The gummy wheel repair was bad enough, I don't want to get into gears, timing and all that!

For a 97 board, improving the print driver and character set would be a plus. I doubt the 97 power supply could support a modern thermal printer, but providing a serial port and driver support would help those calculators with dead printers. I wouldn't mind seeing Note text on a real printout either.

Perhaps you'd get about half as many 97 owners interested as you do 67 owners in a replacement board?

[teenix]

(12-26-2019 09:50 PM)Helix Wrote:  Do you plan to add some kind of continuous memory?
If I've correctly understood the manual, saving a program with more than 112 steps requires 16 keystrokes. If registers must be saved too, this number reaches 24 keystrokes (not counting the PRGM/RUN switch). Almost the same hassle is required after power on.

I know this mimics the behavior of magnetic cards, but I think it would be nice to have a short sequence of two or three keystrokes for example, allowing to save the entire state of the calculator in flash memory, and to recover this state after power on.

Anyway, I am impressed by the work you have done. Congratulations!

It's on the cards :-)

Sorry couldn't resist.

Yes I will add on a feature to save the current calculator state to memory and recall it on power on and make it available for a flash update.

cheers

Tony

[Harald]

Thank you Tony for this wonderfull pair of machines!



The 65 PCB also works!
The key debouncing might need a little tweeking. Sometimes I get keys registering twice. Is this faster than on the 67? Or does my 67 just have a better keyboard?

Cheers,
Harald

PS: When I find the time, I will read all the cards I have and store them. You can then put them on your website.

[teenix]

(01-03-2020 12:44 PM)Harald Wrote:  Thank you Tony for this wonderfull pair of machines!



The 65 PCB also works!
The key debouncing might need a little tweeking. Sometimes I get keys registering twice. Is this faster than on the 67? Or does my 67 just have a better keyboard?

Cheers,
Harald

PS: When I find the time, I will read all the cards I have and store them. You can then put them on your website.

Great news indeed :-)

I'll have a look at the code and tweak the key scan.

cheers

Tony

[mfleming]

(01-03-2020 12:44 PM)Harald Wrote:  PS: When I find the time, I will read all the cards I have and store them. You can then put them on your website.

An excellent idea for when the card readers on these Old Masters eventually become unrepairable.

[teenix]

Hi all,

I am pleased to announce I have posted the availability of the HP-65 replacement CPU board at http://www.teenix.org.



I would like to give thanks to Harald for some advice and helping with the testing of these two boards. It made the job a lot easier.

Also a special work of thanks to Paul Dale. Without his help the project would never have started. He was very generous in lending me some calculators that I could use to "dissect" the innards and develop the circuit boards and code. This has taken longer than I thought so I thank him for his patience as well.

cheers

Tony

[albertofenini]

Hi Tony
wonderful job, congrats,
I have sent you a message from the website http://www.teenix.org but may be it didn't reach you,
what are the options for a shipment other than the one offered ?
Can I have it shipped with full tracking ?
Thanks for your reply.

Note : If this post is inappropriate please remove it

[teenix]

(01-08-2020 01:14 PM)albertofenini Wrote:  Hi Tony
wonderful job, congrats,
I have sent you a message from the website http://www.teenix.org but may be it didn't reach you,
what are the options for a shipment other than the one offered ?
Can I have it shipped with full tracking ?
Thanks for your reply.

Note : If this post is inappropriate please remove it

PM sent.

cheers

Tony

[Hans-Peter]

My 65 is back among the living in my office. I had never imagined the repair to be that easy. I was even able to reactivate the magnetic-reader head after removing the silicone and soldering the missing wire back on.
We, the beneficiaries, are very grateful to Tony.
   
Best regards
Hans Peter

[teenix]

(01-21-2020 09:18 PM)Hans-Peter Wrote:  My 65 is back among the living in my office. I had never imagined the repair to be that easy. I was even able to reactivate the magnetic-reader head after removing the silicone and soldering the missing wire back on.
We, the beneficiaries, are very grateful to Tony.

Best regards
Hans Peter

Such good condition, glad to see it working again.

cheers

Tony

[teenix]

Hi all,

I decided to have a go at making a HP-55 CPU replacement board and as of today it seems to be running ok.

Image below.

The module will run with the HP-55 crystal in place, or if the crystal is broken you can tell the PIC to output 784KHz from one of its IO pins to provide a clock source to the anode driver once the HP crystal has been removed. The PIC is running from its own crystal so the frequency should be reasonably stable for the timer.

The clock signal appears on one of the unused pins on the keyboard and a small wire is required to be soldered from there to a solder pad for the now vacant crystal.

I have put some memory on the module to store up to 100 programs which can be transferred via Bluetooth to a PC.

I was playing with the 55 emulator and I can use one of the unused programming codes to load one of those programs into HP memory while a program is running. I'm not sure if this is useful as you cannot GTO outside the normal program memory space and each new program would start at step 1. Still you could have a program that is made up of 4900 steps.

The emulator can also use the key sequence [f][BST] to clear the program memory when in PRGM mode. I still have to add this to the CPU board.

These changes do not affect the original HP-55 Microcode.

I have also started to put together a small crystal controlled circuit for the HP-45 timer. It only has a few components, so may go for around $Aus10.00 if anyone is still interested in such things.

cheers

Tony

[Massimo Gnerucci]

Tony, you are amazing.
So I will wait for the 55 before ordering 65 & 67 boards.

Thanks a lot.

[Helix]

As for me, I will wait for the pseudo-continuous memory before ordering a 67 board.

(12-27-2019 03:38 AM)teenix Wrote:  Yes I will add on a feature to save the current calculator state to memory and recall it on power on and make it available for a flash update.

[teenix]

(01-24-2020 10:39 PM)Helix Wrote:  As for me, I will wait for the pseudo-continuous memory before ordering a 67 board.

(12-27-2019 03:38 AM)teenix Wrote:  Yes I will add on a feature to save the current calculator state to memory and recall it on power on and make it available for a flash update.

I've been looking into that and it will need a hardware modification. The power for the calculator is controlled by the On/Off switch so a separate battery wire is required and some extra circuitry to keep the PIC memory powered when it is turned off.

cheers

Tony

[Helix]

I was thinking about something simpler.
For example, after a long press on the g key, the message "STO OR RCL ?" would be displayed. Then the STO key would save the entire status of the calculator in flash memory, and the calculator could be manually switched off.
After power on, a long press on the g key followed by the RCL key would recover the last status of the calculator. Only two keystrokes, easy to remember.
I would be happy with something like that. This would also benefit existing boards.

[teenix]

(01-25-2020 01:20 PM)Helix Wrote:  I was thinking about something simpler.
For example, after a long press on the g key, the message "STO OR RCL ?" would be displayed. Then the STO key would save the entire status of the calculator in flash memory, and the calculator could be manually switched off.
After power on, a long press on the g key followed by the RCL key would recover the last status of the calculator. Only two keystrokes, easy to remember.
I would be happy with something like that. This would also benefit existing boards.

I was going to add an addendum to my post and mention that I have been thinking of adding the functionality with a top level menu item. I've been crook with the flu for a couple of days so will get to it soon. For older versions it will be a software update to implement.

cheers

Tony

[Helix]

Great! (the functionality, not the flu).
Get well soon!