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This is a page to discuss adding 5V support to the PCMCIA slots. It is entirely possible, as we understand from the lucent document on VoIP. There is 5V present in the phone. It may be as simple as a jumper wire or it may be as complicated as adding new logic to the PCMCIA driver in addition to some hardcore soldering. Also, it might be possible to add reset as well. Perhaps we'll have to harness some unused GPIO pins to do logic stuffs...

Links to documents on PCMCIA spec, pinouts, etc: Maxim 3.3/5v 2 slot pcmcia power controller (maybe there's something similar in shannon) http://pdfserv.maxim-ic.com/arpdf/MAX780.pdf

TimRiker adds: Shaggy has a 5v enabled phone. I'd love to get it and document from there. Lucent did the hack, but can't seem to get sign off on releasing the docs. I don't know if a modified phone will still support 3.3v cards.

SidFlask adds: Received an answer from Lucent. The info needed to do the changes are at this page: http://erire.com/eshan/ FINALLY!!

ErikAndersen adds: KenMcGuire (a.k.a. GPSFan ) figured out a cool new way to implement the 5V PCMCIA hack. This one is very easy to implement. I implemented this on my phone tonight and it works for me. I had to solder three wires and a switch and it works! I've posted a few (somewhat fuzzy) pictures at http://www.codepoet.org/pcmcia/

KenMcguire adds: The mod ErikAnderson did to his phone was a bit different than the picture below. He didn't have any diodes, so he wired up the other position of the SPDT switch he had to 3.3V. So instead of the diode providing 3.3V he let the switch. This is actually somewhat better for the 3.3V cards since it doesn't have the voltage drop of the diode in the VCC line. BTW, Blue is 3.3V in the picture, and Yellow is 5V. Top refers to the top PCMCIA socket when the Tux in its normal operating position. You can mod either slot or both.

FPascal adds: I tried something a little different. Since I only have 5v cards I did not include the diodes and only wired for 5v operation. Every 5v card that I have tried has worked including my Fujitsu 340Mb PCMCIA harddisk.

KenMcguire adds: To get rid of the nasty Bad VCC error message, change sa1100_shannon.c. Changing state_array->state[1].vs_3v=1 to =0 tells the OS that the bottom slot is a 5v slot. This allows some card drivers to load since they do not get "Bad VCC" messages anymore. (state_array->state[0].vs for the top slot). I hardwired both of my slots too, I've only had trouble with an Epson EEN10B ehternet card, but MHz ethernet, Integral 170MB HDD, Iomega Clik, SmartMedia, CompactFlash, all work fine.

RedBeard adds: Here is a more detailed how-to for a 5v only hack. http://www.xmission.com/~redbeard/tuxscreen-5v-pcmcia-hack/index.html

Here is Ken's picture: http://tuxscreen.net/download/schematics/5Vx2.jpg

Se also the PCMCIAHack for another method.

KenRestivo adds: found this picture, too, and find it quite a bit clearer.


* the black and striped wires at the top are for a keyboard mod, NOT for pcmcia. But the two blue wires are what to be done to get 5V PCMCIA going, along with the removed resistors R337 and R338 that you can see quite clearly in this picture.

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