HP97 The journey begins

[teenix]

Hi all,

The Spice is almost there (tongue in cheek) Way more work than I originally thought. The 34C is shown in the image but the module has selectable 31E, 32E 33C, 34C 37E and 38C.

The keyboard had some issues and turned out to be a poor design for the circuit board pad contact area and only hard key pressure would work. They were redesigned and now seems ok to use. The original keys may have worn a bit over the years so I don't think it will be as good as new, but the new membrane pads feel quite good. The back case also seems happy when attached with the new innards.

The display is a tiny bit dimmer than the original. The extra circuitry required to power it with external drivers (which have to be discrete parts) was not going to fit in the board space available, so they have been omitted. I doubt it will make much difference and maybe the slight drop in LED current might prolong their remaining life.

I will connect the battery board soon and make sure the USB charger is working and the battery is powering everything ok. There is a bypass circuit added to the charger so the calculator should work while on charge.

The PC software has been updated to recognize the Spice. Just have to do a full test and see that the software is behaving and update the help file.

Install should be pretty easy. There is no soldering required, so once the original is disassembled, it should take a couple of minutes to insert the display and click the board into place and then put the back cover on.

I am not going to supply the battery and USB charge cable. They can be found on the web for a few $.

cheers

Tony