Using circuit board from an old PS2 keyboard to make a custom, easy to use Prop
WBA Consulting
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About 2 years ago, I made a custom setup to display work instructions for an operator at a mechanical assembly station at work. The setup consisted of a Wyse 9650XE Thin Client that is running Windows XP embedded. The 9650xe is basically a 15" LCD wearing a VIA Mini-ITX 500Mhz motherboard as a backpack. The work instructions in PDF format were copied to a memory stick placed into the USB port. The circuit board from a PS2 keyboard is plugged into the PS2 port. I hardwired the contacts corresponding to the left and right arrow keys to an on-off-on momentary toggle switch that I mounted in the front of the case where the Wyse logo was glued on. The unit would be powered up and a lead operator would plug in a USB mouse to navigate to the proper PDF file. After opening it up, the lead pulls out the mouse and the operator only has the toggle switch as an input device. To advance a page, the operator pushes the toggle switch to the right, to go back a page, pushes it to the left. It works rather well. If anyone is interested in seeing pictures of it, I can take some when I go back to work next week.
Anyhow, as I was digging through my junk boxes for my most recent project, I saw that I had several PS2 circuit boards that were pulled from a bunch of keyboards I bought off of eBay. Now that the propeller takes up most of my free time, I thought that they could be used to make a custom keypad for anything and the keyboard.spin object could be used as the software interface. Basically, I could wire up any momentary switch as a "key" to the PS2 circuitboard. One thought is making a PS2 protocol, 4 button capacitive touch keypad by merging a PS2 circuitboard with my Qtouch QT240 demo board.
Shouldn't this be an easy way to provide custom input devices to the propeller? Instead of worrying about a matrix setup, etc, just use 2 pins for PS2 protocol and you have up to 101 keys. Yes, I know it's still a matrix setup off the PS2 board, but that saves the Prop from using pins for the matrix.
Will there be a speed difference with looking for keypresses from the PS2 port as opposed to scanning the I/O pins of a key matrix?
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Andrew Williams
WBA Consulting
WBA-TH1M Sensirion SHT11 Module
Special Olympics Polar Bear Plunge, Mar 20, 2010
Anyhow, as I was digging through my junk boxes for my most recent project, I saw that I had several PS2 circuit boards that were pulled from a bunch of keyboards I bought off of eBay. Now that the propeller takes up most of my free time, I thought that they could be used to make a custom keypad for anything and the keyboard.spin object could be used as the software interface. Basically, I could wire up any momentary switch as a "key" to the PS2 circuitboard. One thought is making a PS2 protocol, 4 button capacitive touch keypad by merging a PS2 circuitboard with my Qtouch QT240 demo board.
Shouldn't this be an easy way to provide custom input devices to the propeller? Instead of worrying about a matrix setup, etc, just use 2 pins for PS2 protocol and you have up to 101 keys. Yes, I know it's still a matrix setup off the PS2 board, but that saves the Prop from using pins for the matrix.
Will there be a speed difference with looking for keypresses from the PS2 port as opposed to scanning the I/O pins of a key matrix?
▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
Andrew Williams
WBA Consulting
WBA-TH1M Sensirion SHT11 Module
Special Olympics Polar Bear Plunge, Mar 20, 2010
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