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I have managed to piece together a pretty cheap and easy to setup DISPLAY option for the HP-75c and HP-71b.

I use the following parts:

- J-Fs Pil-io
- ESP8266 proto board
- Logic converter for 5v to 3.3v
- breadboard
- ESPTerm firmware from esptetm.github.io/term.html
- esp flash tool

What you can do after flashing espterm firmware and setting up your espterm WiFi , is log into a browser and navigate to the terminal window, type DISPLAY IS :PILSER1D or equivalent and you have a working display in your browser. It seems to parse most of the output pretty well. The HP-75c works almost flawlessly and the KEYBOARD IS also works so you can use your desktop keyboard to control the HP-75c.

A couple of photos are attached.

The DISPLAY IS also works pretty wrll for the HP-71b with the exception of the arrow keys. The KEYBOARD IS also does not work with this setup as explained by J-F in my recent post.

https://www.dropbox.com/s/rutudh9r9el9sp...1.jpg?dl=0

https://www.dropbox.com/s/hp9b0ii1mez2t9...0.jpg?dl=0

https://www.dropbox.com/s/330bzs6zizlnnd...3.jpg?dl=0

Cheers
Cool! Certainly more convenient than dragging out a monitor... though of course ILPer and pyILPer need less h/w. Still, I like it!

Is there any chance you will offer a few of these for sale?

I will get in line now, waiting for your reply...

PM or email reply if you prefer.
Hi Bob

I am happy to provide details on how to put it together. Not something I can build and sell as it includes HP-IL cables and J-Fs pil-box.

If J-F could tweak the pil-io firmware to handle the HP-71b service request it would make a great add on when you buy a pil-ioWink

It’s quite cool being able to use your iPad as a screen for a vintage calculator.

Richard
(08-31-2019 11:29 PM)coitboy2000 Wrote: [ -> ]Hi Bob

I am happy to provide details on how to put it together. Not something I can build and sell as it includes HP-IL cables and J-Fs pil-box.

If J-F could tweak the pil-io firmware to handle the HP-71b service request it would make a great add on when you buy a pil-ioWink

It’s quite cool being able to use your iPad as a screen for a vintage calculator.

Richard

I have HP-IL cables and can arrange to get the needed PIL-IO from JFG. I'll contact you by email about the other parts, etc.

Thanks for posting this here Richard. Indeed, very cool.
No worries. I will message you the parts list. It is very straight forward.

Richard
(09-01-2019 07:08 AM)coitboy2000 Wrote: [ -> ]No worries. I will message you the parts list. It is very straight forward.
Hello Richard,
I already have two PIL-IO boards (firmware 2.0) and lots of HP-IL cables.
I would like to build your project and would appreciate if you could send me the part list.
I am sending you a PM with my email address.
Thank you!
Sylvain
(08-31-2019 11:29 PM)coitboy2000 Wrote: [ -> ]If J-F could tweak the pil-io firmware to handle the HP-71b service request it would make a great add on when you buy a pil-ioWink

(09-01-2019 11:25 AM)Sylvain Cote Wrote: [ -> ]I already have two PIL-IO boards (firmware 2.0) and lots of HP-IL cables.
I would like to build your project and would appreciate if you could send me the part list.

Since this makes 3 persons interested, it's worth to release a firmware 2.1 :-)

Sylvain, I know that you have the equipment to reprogram the PIL-IO firmware, so when you will have the project ready let me know and I will send you a hex file for test.

J-F
I'm interested in your project too.. Part list would help Smile
Hi All,

Here is a list of the parts I used, embarrassingly simple.

1. A pil-IO from http://www.jeffcalc.hp41.eu/hpil/index.html#pilio that is where the real magic happens. Also need HP-IL cables obviously.

2. An ESP8266 12F development board from https://www.altronics.com.au/p/z6381-wif...ent-board/ or similar. You could save $$ by using an existing RS232 to usb cable to flash the device but this is a simple option. Also much cheaper on ebay but this link provides a good picture & description.

3. A logic level converter board https://www.altronics.com.au/p/z6390-3.3...ter-board/ Someone may be able to advise whether this is actually needed or not ? Given the ESP board is 3.3v and the Pil-IO is 5v I decided not to risk it.

4. A power supply like https://www.altronics.com.au/p/z6355-3.3...er-supply/ You have many alternatives to choose from here. Both the Pil-IO and ESP board can accept 5V to power them.

5. Firmware to flas on the ESP8266 from https://github.com/espterm/espterm-firmware or more specifically the link https://github.com/espterm/espterm-firmware/releases It would be great if someone could learn how to compile the source in Windows or Linux so the escape sequences etc can be tweaked in the code. i.e. UP arrow on HP-71b

6. ESPFlash tool from https://www.espressif.com/sites/default/....6.7_1.zip this link has the Windows version.

7. Jumper leads and solder etc

8. Breadboard or prototyping board if desired.

I have attached an image of the flashing tool for the ESP8266 to assist. You need to press the flash button and reset button on the ESP8266 device to get it into the correct mode for flashing. Power off and restart then follow the ESPTerm instructions on GitHub. You need to use a Wi-Fi device (not your phone though in my opinion) to connect to the Access Point created by the ESP8266 and then browse to 192.168.4.1 to set it up properly.

Hope this is clear enough.

Cheers
That is exciting news J-F. Smile

Richard

(09-01-2019 01:18 PM)J-F Garnier Wrote: [ -> ]
(08-31-2019 11:29 PM)coitboy2000 Wrote: [ -> ]If J-F could tweak the pil-io firmware to handle the HP-71b service request it would make a great add on when you buy a pil-ioWink

(09-01-2019 11:25 AM)Sylvain Cote Wrote: [ -> ]I already have two PIL-IO boards (firmware 2.0) and lots of HP-IL cables.
I would like to build your project and would appreciate if you could send me the part list.

Since this makes 3 persons interested, it's worth to release a firmware 2.1 :-)

Sylvain, I know that you have the equipment to reprogram the PIL-IO firmware, so when you will have the project ready let me know and I will send you a hex file for test.

J-F
(09-03-2019 11:03 AM)coitboy2000 Wrote: [ -> ]That is exciting news J-F. Smile

Richard

(09-01-2019 01:18 PM)J-F Garnier Wrote: [ -> ]Since this makes 3 persons interested, it's worth to release a firmware 2.1 :-)

Sylvain, I know that you have the equipment to reprogram the PIL-IO firmware, so when you will have the project ready let me know and I will send you a hex file for test.

J-F

Now four persons :-)

Best regards
Erwin
(09-01-2019 01:18 PM)J-F Garnier Wrote: [ -> ]Sylvain, I know that you have the equipment to reprogram the PIL-IO firmware, so when you will have the project ready let me know and I will send you a hex file for test.
Perfect, I will let you know when I am ready.

(09-02-2019 09:57 AM)coitboy2000 Wrote: [ -> ]Here is a list of the parts I used, embarrassingly simple.
Thank you!

The next two weeks will be a challenge to have time for this project but I should have some after HHC2019.

Sylvain
One thing I have noticed with this setup is that you cannot edit a line of code on the display. I.e. With the HP-75 connected, pressing the up arrow brings up a line of code on the wifi display but the cursor is not in the same position as it is on the Hp-75 and further arrow movements sideways etc are not recorded on the wifi display. I am not sure if this is standard behaviour on a CMT display? Thought I would mention it as it may be a deal breaker for some.
After 3 nights trying to get the espterm source code to compile on Linux I have managed to get it working.

For those who are interested I have modified the ESC codes and you can now edit on the wifi screen just like you do on the calculator !! Happy to post new ESP8266 binary files to flash for those who are interested. What a difference that makes.

Youtube

(09-03-2019 09:29 PM)coitboy2000 Wrote: [ -> ]One thing I have noticed with this setup is that you cannot edit a line of code on the display. I.e. With the HP-75 connected, pressing the up arrow brings up a line of code on the wifi display but the cursor is not in the same position as it is on the Hp-75 and further arrow movements sideways etc are not recorded on the wifi display. I am not sure if this is standard behaviour on a CMT display? Thought I would mention it as it may be a deal breaker for some.
(08-31-2019 10:26 AM)coitboy2000 Wrote: [ -> ]The HP-75c works almost flawlessly and the KEYBOARD IS also works so you can use your desktop keyboard to control the HP-75c.

Hi,

I know that the KEYBOARD IS command is part of the HP-75 IO ROM, but I have not found a LEX file for the HP-75 (NOT THE 71B, I have that) with the KEYBOARD IS command.

Anybody knows if such a LEX file exists?

thanks

**vp

http://www.series80.org
(09-21-2019 10:24 PM)vassilisprevelakis Wrote: [ -> ]I know that the KEYBOARD IS command is part of the HP-75 IO ROM, but I have not found a LEX file for the HP-75 (NOT THE 71B, I have that) with the KEYBOARD IS command.
Anybody knows if such a LEX file exists?

I don't know such LEX for the 75, but since we have the I/O ROM sources, it could be a nice project to build a standalone KEYBOARD IS LEX file, using the HP85 assembler.
As for the HP85, adapting a ROM keyword to a RAM-based LEX requires some precautions, such as replacing the absolute JMP/JSR with indexed versions, and maybe other changes that I don't remember/know.

J-F
The IO-ROM consists of 3 ROMs (LEX numbers 0x4063 0x4064 0x4065). The main part of the KEYBOARD IS command is in the first ROM, but it refers at least to one routine in the second ROM. This should be combined into a single LEX file.

The ROM images can be disassembled with Everetts disassembler - I have done this only for the first ROM and can provide the listing as a starting point.
Comments for the code can be found in the printed IO-ROM listings, but these listings use macros from the KARMA HP-1000 assembler (like IF/THEN/ELSE) which are not available in the HP-85 assembler.
Therefore I prefer to disassemble the original ROMs and use the printed listings as a guideline for comments.

Note for hardware experts: It would still be interesting to design a modern ROM emulator for the HP-75 ... if the connector problem can be solved.

Martin
(09-24-2019 07:49 AM)Martin Hepperle Wrote: [ -> ]if the connector problem can be solved.
I have asked Chuck McCord (part of the HP-75C development team) at HHC2019 and he confirmed that the connector was a custom order from HP.
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