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
(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
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
(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...
(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
(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
(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
(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
Pauli
(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
(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 :-)
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
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]](http://www.teenix.org/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
The bottom row will require hardware support, the rest look straightforward.
Pauli
(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
(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
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
(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
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