Re: Newbie needing keyboard splitter advice

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: : Sorry for the long post, but I'm almost in too deep on this. : : On the BYOAC site, it shows an easier to build keyboard splitter than Stephan Han's design, but says that it has several disadvantages that Steven's design doesn't. Has anyone built one, or does anyone know what these are? : I'm not sure, but the easy to build one looks as if commands going from the PC to the keyboard will go to the keyboard that last sent data to the PC (the cross coupled NAND gates are an RS Latch). As far as I know this would mainly affect turning on and off the keyboard LEDs. I think Stephen Hans splitter will send all of the commands from the PC to one of the two keyboards. : : : I am thinking of using a solderless breadboard (Radio Shack #276-175) for the circuit. Anyone used one? Good or bad idea? (I don't like soldering.) : Solderless breadboards are great for prototyping, but it is pretty easy to accidentally pull wires out of them by accident. They're also kind of expensive by comparison. If you have it enclosed in something, it may work out allright. Use solid wire to make the connections. Stranded wire doesn't work too well in them, (unless you tin it with a soldering iron, but then you might as well solder it on a breadboard). : : The sockets are labelled CW 3 5 2 4 1 for both circuits. I assume that this is looking from the cable side in on the receptacle (looking at it the way the cable would be inserted). Is this correct? : Yes, DIN socket numbering is confusing. I think you have it right for the sockets. : : : The IC's are shown with numbered terminals. Looking down on the IC, are they usually numbered: : : 1 2 : : 3 4 etc : : or : : 1 7 : : 2 8 ? : Chips are pretty easy, but the Pin 1 markings vary from manufacturer to manufacurer. Sometime there is a dimple next to pin one, sometimes there is sort of a "U" shaped indentation on the end of the chip that has pin one, and every now and then it is just part of the printing on the device. : Once you find pin 1, the pin next to it is pin 2, then pin 3 and so on along the edge. Once you run out of pins (on a 14 pin dip, once you get to pin 7, you cross directly over the chip to pin 8 and continue numbering (CCW). In other words, on a 14 pin dip you count down the left side from pin 1 to 7, and count up the right side from pin 8 to pin 14. That is to say, pin 1 and 14 are opposite each other, and pin 7 and 8 are opposite each other. : : : On the simpler circuit, is IC2A and IC2b two halves of one 4093 chip, or are two 4093 chips required? : Two halves of the same chip. : : The simpler circuit shows +5V and ground coming into the circuit. Can I just get this from pins 4 and 5 of the input cable? : : Yes. You shouldn't need an external supply. The computer will supply the voltage. : : Digikey sells a M-F coiled keyboard extension cable. Does anyone know a source for a M-M keyboard cable? Andy Warne sells them with the I-PAC, I know I can order one from him. : : Does anyone know a source for a female - female DIN 5 keyboard connector (barrel style)? : : Thanks in advance for any suggestions! : : Good luck.

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