combining hp41 modules into one cartridge

[twdeckard]

Greetings. Can someone point me to any documentation on shoehorning two ROM circuits into one cartridge? I recall a French article that described how careful soldering and perhaps a little sandpaper could put two 4K ROMs in one package.

Also, for someone expert in this manuever can you put an Extended Memory together w a 8K ROM because the address spaces don’t overlap?

Thanks
Todd
https://github.com/twdeckard/HP41CX-SLANTR?files=1
https://github.com/twdeckard/HP41CX-PLAN...PLAN41.rpn (doomed to
remain incomplete and undebugged)

[Mark Hardman]

(02-13-2018 02:19 AM)twdeckard Wrote:  Greetings. Can someone point me to any documentation on shoehorning two ROM circuits into one cartridge? I recall a French article that described how careful soldering and perhaps a little sandpaper could put two 4K ROMs in one package.

Also, for someone expert in this manuever can you put an Extended Memory together w a 8K ROM because the address spaces don’t overlap?

Thanks
Todd
https://github.com/twdeckard/HP41CX-SLANTR?files=1
https://github.com/twdeckard/HP41CX-PLAN...PLAN41.rpn (doomed to
remain incomplete and undebugged)

This thread in the old forums section would be a good place to start:

Double Extended memory module HP41cx..

PeterP references specific issues of PPC:

PPC V11N1 p28 - Procedure for Module Doubling/Tripling
PPC V13N7 p21 - Procedure for Module Doubling/Tripling

If you don't already have a copy of the PPC DVD, it can be purchased for a modest amount from Jake Schwartz at http://www.pahhc.org/ppccdrom.htm.

[Craig Bladow]

I plan to do this with two extended memory modules, but I’m going to combine two single density memory modules first, so I have a better chance of success with the extended memory modules.

[Nate Martin]

try this:

http://www.hpmuseum.org/guest/klug/dblxmem.pdf

[damaltor]

if you succeed, i would be interested in the empty module shell and connector. Good luck on your project. the pdf linked by Nate Martin is probably the best starting point.

[Nate Martin]

(02-13-2018 07:49 AM)damaltor Wrote:  if you succeed, i would be interested in the empty module shell and connector.

3D printed Module shells can be found at:
https://www.shapeways.com/product/LSV44R...-inventory

[twdeckard]

Thanks!

[damaltor]

(02-13-2018 09:22 PM)Nate Martin Wrote:  

(02-13-2018 07:49 AM)damaltor Wrote:  if you succeed, i would be interested in the empty module shell and connector.

3D printed Module shells can be found at:
https://www.shapeways.com/product/LSV44R...-inventory

Thanks, i have seen that. Still the original shells are nicer, and the connector is hard to build from scratch