|Rewiring Handheld Products Card Reader RAM|
Message #1 Posted by Mike on 20 May 2006, 10:24 p.m.
I wonder if it's possible to add memory capacity to a 32K Handheld Products RAM, for instance. The Handheld products 32K RAM/EPROM has space for an EPROM, so it seems likely that one could use the space to add some additional RAM. Now, the EPROM wouldn't likely have a WR signal to it but that should be easy to find.
I also wonder if it's likely that they used the same controller for their 32K RAM as they do for their 128K RAM. If so, it should be able to add another 96K of RAM, one would think, with some creative piggybacking.
Also, there is a jumper that has 2 positions, plus a position with no jumper applied, giving 3 possible settings. Anyone know what this jumper is for? Might it be for different RAM configurations? Or, it might be for different sizes of EPROMs. Just curious about this.
As far as I can tell, there is only RAM, EPROM and the controllers. It appears there might be a seperate controller for the EPROM and one for the RAM. Both are on different boards. There is a RAM board and an EPROM board. So, unless the controller is different for each RAM Module size or between RAM and EPROM, it should be possible.
Anyone know if there is any article on reworking a Handheld Products RAM device?
Edited: 20 May 2006, 10:47 p.m.