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Basic Electronics » Help re-purposing A Palm M100 Portable Keyboard.

September 17, 2011
by Twarter369
Twarter369's Avatar

Hey again. I have a Palm Brand Portable Keyboard. It has a 10 pin header that slides into the bottom of a Palm M100. I read which is for the PIC. No biggie, I should be able to convert most of it to C. I am also using as my information to the pin out of the header.

My questions are: 1) Can I have multiple devices hooked up to RxD and TxD? I know that the LCD uses it, and the Keyboard will also need it. So is it either or? 2)RTS and CTS are used to request and grant permission respectively. Does this mean I need to hook RTS to an external Interrupt pin? and when I sense a pin change I need my code to set the pin CTS is hooked up to, right? After I flip CTS, I need to read the char(s) that come in on the uart stream, correct?

Any other information or relevant reading you all can suggest will be appreciated. Also, as usual, code snippets that accomplish this (or close) are also greatly appreciated.

September 18, 2011
by Rick_S
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The LCD doesn't use the RX/TX lines of the micro-controller in a standard NK setup. Scanning over the WB9KZY site, it appears the keyboard you are asking about is simply a serial interfaced keyboard... Which means you can attach it to the micro w/o any external hardware other than possibly a 3.3v power source.

As for your questions, you probably could piggyback two tx lines into the micro as long as they weren't both sending at the same time. You could also probably piggyback two RX lines from the TX of the micro. You may run into issues though because of too much voltage drop with multiples... not sure haven't tried it. As for RTS/CTS, you may not need them (unless the kbd requires it). Depending on your application, you may just poll the uart for data. (see the uart.c library in the libnerdkits folder).

What are you wanting to do with the keyboard? Are you wanting to build a morse code generator like the sample program you linked? If not, a lot of that code will be irrelevant.


September 18, 2011
by Twarter369
Twarter369's Avatar

My mistake, I meant the USB uses the RxD/TxD, which shouldn't be a problem for me. At first I just want to get the character sent to the LCD. Ultimately though, it will end up being used as the keyboard for a portable wireless network testing station I am building. 12 802.11 USB wireless adapters will be in monitor mode on different channels. I plan on running the setup from a MSI 890GXM-G65 board with: an AMD Phenom II, 32G SSD, 2x2G DDR3 RAM. The whole setup will be running an automated (and lighter weight) version of BT5. I will be gutting everything but the necessities to run aircrack-ng

Before anyone freaks, I am working on becoming a C.I.S.S.P. and C|EH. I really don't plan on using my setup for war-driving. This is purely for proactive network testing and defense.

The form factor for the project is a standard toolbox from Stanley. When the lid is open I will be able to deploy any/all of the 12 antenna. In the main compartment is where I will keep my Board, Power Supply (starting with a standard +45w but I want to move to an optional battery setup later), and cooling fans (intake and exhaust). Okay I know I wrote a novel, but any tips people could give me on this type of setup would be appreciated.

ALSO if anyone has plans for a wi-fi pineapple, I would sure love to look at them, I want one like they sell on Hak5, but I'd rather get my hands dirty than pay $40-60 for one.

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