This is the schematic circuit for the front panel of project Redwood. http://forums.bit-tech.net/showthread.php?t=86002 I actualy had this finished and posted at the LCDForums since March 17th. This is not the touch-wheel circuit, that will take longer. ------------------------------------------------------------------------- I am offering my schematic up for anyone to pruse through. (Educational, Non-Commercial use only!) Sorry for no actual values on components. This circuit is untested. I won't do too much explaining, you can either read it, or you can't. If you notice a screw-up though, please tell me. The faceplate will have four indicator lights/buttons on the front of the box. http://www.zapwizard.com/Projects/wood/version3/11.jpg POWER - DVD - IDE - WIFI The buttons are touch-sensative via a QTouch IC (www.qprox.com) The output of the QProx is connected to an opto-isolator, as the Qtouch IC is sensative to voltage spikes and power loads. The QTouch is powered from +5volts standby (To allow for power-on) The output of the Opto drives four relays which are connected to the Matrix Obital LCD keypad input. The opto output is also hardwired to drive Motherboard power on, and DVD Eject. Windows can be programed to ignore the power button once booted. This allows me to use it to pull up a display on the LCD. There are four tiny lights above the buttons that are more for decoration then anything. But through some diode trickery, they will be wired so that when you press the button below, the LED above turns off, providing an feddback indicator when you press the button below. All the front panel LEDs can be driven by a High Power PWM Output on the Matrix Orbital, allowing for dimming, without loosing functionality. There is also a jumper for pure +12volts. I will use another PWM output of the LCD to control the case feet lights. The motherboard's own PWM controls will control the radiator fans and waterpump. There are four input LED signals, these allow for connection of Power, IDE activity, DVD Activity, and WIFI Activity signals. These inputs drive an Opto directly to isolate them from the circuit. The four indicator LEDs will be used to back-light the buttons, and will remain on when the input signal is inactive. (Inverted) This is done by shorting the LEDs out via the Opto's transitors. An additional resistor will ensure that when active the LEDs will not turn 100% off, but will rather flicker and dim when active. In the final build I may install jumpers that will allow either the back-lit button LEDs, and the small point lights to be swapped. LCD Functionality: Since all four buttons are also wired to the LCD keypad inputs, I can make them interactive. For example, press the DVD Eject button, the DVD ejects and "DVD Ejecting" is displayed on the LCD. For Power, IDE, and WIFI I am making different stat's screens pop-up. Press Power and the LCD goes into a demo program, listing system specs, and infromation. (For people to read at a LCD for example) Press IDE and the system checks the weather, displays the harddrive, memory, and CPU stats, along with the weather info. Press WIFI and the system checks e-mail, displays how many e-mails there are, then lists the network stats such as IN/OUT totals, IP address, etc... I already purchased LCDC and have programed the above funtions in and tested some of the circuit. I am working on the PCB design right now.
Curious about the relays you used. I take it they are small ones, that way they aren't that noisy. But how come you didn't use something solid state? Is it something in how the LCD detects the button presses?
I will be using tiny single-in-line package reed relays. They should make no noticable noise at all. I would prefer transistors, but the LCD keypad is meant to be connected to matrix of normal switches, and transistors would not work as reliably.
The 7805 iirc has a minimum voltage drop of about 2V or so - so you won't be getting a 5V output with a 5V input. The 5V standby I except should be clean enough with a couple capacitors to use without regulation. edit: lol beaten by seconds
Oh - the reset line is wired wrong as well - both the resistor and the capacitor should be connected to pin 28, and the capacitor should also be grounded.
The Qprox can run on 3volts, in which case I need to replace that regulator with a 3 or 3.3 volt model. Basicly they state in their spec sheets that a regulator is needed as close as possible to the IC as they are sensative to voltage spikes. I can also just add a jumper with cap so I can switch between regulated, and non-regulated Thanks, I'll fix that. I am working out the PCB right now. The Qtouch IC needs to be as close to the sensors as possible, so I will make a small board to hold that part of the circuit (and opto) The rest of the PCB will be sized to mount onto the bottom of the system harddrive. I have a new schematic too with the above fixes, and I added headers for the case feet lights, and DIP switches to control the Touch lights and points lights. I will upload it later.
For the "not too technicaly inclined" audience, if you should happen to ever find the time...I think it would be most beneficial to a lot of people if you could post all the part values
