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Paul Dale · 04-18-2020, 08:20 AM

The scope trace is very pretty and interesting.

Is there a timer that can be used to produce the 10kHz modulation? Without that, it will be quite a challenge.

Pauli

teenix · 04-18-2020, 09:16 AM

(04-18-2020 08:20 AM)Paul Dale Wrote: The scope trace is very pretty and interesting.

Is there a timer that can be used to produce the 10kHz modulation? Without that, it will be quite a challenge.

Pauli

The hardware is getting a work out :-)

cheers

Tony

teenix · (This post was last modified: 05-01-2020 05:38 AM by teenix.)

Hi all,

I received some circuit boards the other day so international postage is still working to a degree :-)

I decided it should be ok to submit the HP-97 replacement CPU prototype designs for manufacture, of which two are required, and hopefully I'll have them in a few weeks to begin populating and testing - exciting.

The 64 pin TQFP chip (pin spacing 0.5mm) might be a challenge to solder but I think it should turn out similar to the 44 pin chips used in the other boards which are quite easy.

Edit: Some other circuit boards came today for another HP project I've been playing with which uses the same PIC, and it looks like these chips can be soldered with simple tools from home :-)

cheers

Tony

**rprosperi** · 05-01-2020, 11:54 AM

(05-01-2020 03:47 AM)teenix Wrote: Edit: Some other circuit boards came today for another HP project I've been playing with which uses the same PIC, and it looks like these chips can be soldered with simple tools from home :-)

Well, I guess a few people have such tools at home, and the skills to use them properly, but never, ever mistake that for being typical. You geniuses have such a hard time keeping track of the rest of us... Smile

Hans Brueggemann · (This post was last modified: 05-01-2020 12:31 PM by Hans Brueggemann.)

no worries, even the "experts" are just cooking with water, solder flux is your friend:
fine pitch soldering done right

teenix · 05-02-2020, 01:54 AM

(05-01-2020 12:29 PM)Hans Brueggemann Wrote: no worries, even the "experts" are just cooking with water, solder flux is your friend:
fine pitch soldering done right

Definitely, although I would like a flux that washed off in water. The ones I've seen need something stronger to clean it up.

cheers

Tony

Harald · 05-04-2020, 09:47 AM

(05-01-2020 03:47 AM)teenix Wrote: Hi all,

I received some circuit boards the other day so international postage is still working to a degree :-)

I decided it should be ok to submit the HP-97 replacement CPU prototype designs for manufacture, of which two are required, and hopefully I'll have them in a few weeks to begin populating and testing - exciting.

The 64 pin TQFP chip (pin spacing 0.5mm) might be a challenge to solder but I think it should turn out similar to the 44 pin chips used in the other boards which are quite easy.

That sounds grerat! I am tempted to take appart my working 97. I probably wont do it though Smile

(05-01-2020 03:47 AM)teenix Wrote: Edit: Some other circuit boards came today for another HP project I've been playing with which uses the same PIC, and it looks like these chips can be soldered with simple tools from home :-)

cheers

Tony

Now I am intrigued. What is this other project you are talking about?

Cheers,
Harald

Paul Dale · 05-04-2020, 09:53 AM

(05-04-2020 09:47 AM)Harald Wrote: That sounds grerat! I am tempted to take appart my working 97. I probably wont do it though

You should do it Smile

Pauli

teenix · 05-04-2020, 10:17 AM

(05-04-2020 09:47 AM)Harald Wrote: Now I am intrigued. What is this other project you are talking about?

Cheers,
Harald

It's in the secret laboratory down in the dungeon at the moment :-)

cheers

Tony

Harald · 05-04-2020, 01:31 PM

(05-04-2020 10:17 AM)teenix Wrote:
(05-04-2020 09:47 AM)Harald Wrote: Now I am intrigued. What is this other project you are talking about?

Cheers,
Harald

It's in the secret laboratory down in the dungeon at the moment :-)

cheers

Tony

OK, I'll try and be patient :-)

Hans-Peter · 05-04-2020, 05:43 PM

Harald Wrote:
That sounds grerat! I am tempted to take appart my working 97. I probably wont do it though Smile

I'm lucky to have a half working 97. So I will do it.
Can't wait for the new pacemaker :-)

Hans-Peter

teenix · (This post was last modified: 05-13-2020 07:59 AM by teenix.)

Hi all,

It will be a bit of an unknown wait for the unpopulated prototype 97 CPU board to be delivered so I thought I might try my hand at a Woodstock replacement CPU board while I'm waiting.

[Image: wsCPU.jpg]

It looks ok so far but will need a lot of work to finalize. The one board will suit all models including Constant Memory types.

I really would like a drop in replacement but there are connectors on the original board that have no replacements these days. Specifically the inter PCB connectors of which there are 2 types fitted to these boards. These will have to swapped over from a dead board which shouldn't be too hard.

You never know your luck tho.

On a side note, does anyone know if it is possible to contact Tom Osborne?

cheers

Tony

AndiGer · 05-13-2020, 04:21 PM

Tony,

When will you go to work on this one?
https://www.hpmuseum.org/item/product2.htm ... LOL :-D

teenix · 05-14-2020, 12:56 AM

(05-13-2020 04:21 PM)AndiGer Wrote: Tony,

When will you go to work on this one?
https://www.hpmuseum.org/item/product2.htm ... LOL :-D

It's possible if you have the algorithms - and buttons and case ;-)

cheers

Tony

Paul Dale · 05-15-2020, 04:22 AM

The bottom row will require hardware support, the rest look straightforward.

Pauli

Harald · 05-22-2020, 09:20 PM

(05-13-2020 07:57 AM)teenix Wrote: Hi all,

It will be a bit of an unknown wait for the unpopulated prototype 97 CPU board to be delivered so I thought I might try my hand at a Woodstock replacement CPU board while I'm waiting.

It looks ok so far but will need a lot of work to finalize. The one board will suit all models including Constant Memory types.

I really would like a drop in replacement but there are connectors on the original board that have no replacements these days. Specifically the inter PCB connectors of which there are 2 types fitted to these boards. These will have to swapped over from a dead board which shouldn't be too hard.

You never know your luck tho.

On a side note, does anyone know if it is possible to contact Tom Osborne?

cheers

Tony

That looks really nice!
The connectors are a little tricky to solder. Getting them all in a straight line is the difficult part. I can't think of a replacement either though.

Cheers,
Harald

teenix · 05-23-2020, 03:39 AM

(05-22-2020 09:20 PM)Harald Wrote: That looks really nice!
The connectors are a little tricky to solder. Getting them all in a straight line is the difficult part. I can't think of a replacement either though.

Cheers,
Harald

Not really original, but using 0.1" header pins/sockets may work. The holes are large in the key and display boards, but they could still be soldered, and maybe more reliable.

cheers

Tony

PANAMATIK · 05-23-2020, 10:36 PM

Great work!

This board was in my mind when I thought about a HP-25 replacement in 2014, before I decided to make only the new ACT chip. Alignment of the contacts shouldn't be difficult. I often accidentally unaligned one or two of them and it was easy to adjust.

What do you use as battery contacts?

And not to forget to ask just for my personal interest:
Is there also Real Time Clock and GPS and Infrared Print, alphanumerical LED Display, 512k Flash memory and Power Down mode included?

This large board space would allow for many many new features, including running Linux or windows on it. Sorry, I apologize for these, they would not be a good idea, perhaps better for today, a self driving car application, or KI based general math solver for functions, which are not yet discovered.

Bernhard

teenix · 05-24-2020, 12:18 AM

(05-23-2020 10:36 PM)PANAMATIK Wrote: Great work!

This board was in my mind when I thought about a HP-25 replacement in 2014, before I decided to make only the new ACT chip. Alignment of the contacts shouldn't be difficult. I often accidentally unaligned one or two of them and it was easy to adjust.

What do you use as battery contacts?

And not to forget to ask just for my personal interest:
Is there also Real Time Clock and GPS and Infrared Print, alphanumerical LED Display, 512k Flash memory and Power Down mode included?

This large board space would allow for many many new features, including running Linux or windows on it. Sorry, I apologize for these, they would not be a good idea, perhaps better for today, a self driving car application, or KI based general math solver for functions, which are not yet discovered.

Bernhard

I have a few HP projects on the go at the moment, so if I follow through, my thoughts are for a bog standard setup, but with memory for program storage.

I have ideas for the hardware connections but working away from home again is keeping me from progressing except for the software.

cheers

Tony

PANAMATIK · (This post was last modified: 05-24-2020 05:01 PM by PANAMATIK.)

Hi Tony,

If it is for any use for your projects, you know that the "HP Low Power" C source code and schematic is free for use and can be downloaded from my website. But I also know, that you have made highly valuable software by yourself and as in so many cases the projects are not compatible by compiler and by approach.

My last project, the SPICE Low Power repair kit, got stuck after I finished everything and made two perfect working prototypes for me and a nice HP-34 LP for someone in this forum. It turned out that is was too difficult to install the SPICE LP circuit into the SPICE calculator by DIY, starting from opening the calculator case and many more traps following. Therefore I couldn't offer the circuit for purchase.

Keep going!

Bernhard