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RFEFX
- 11th January 2011, 23:07
ok, so here are the detailed features of my board.
- The board is based off the PIC16F877A microcontroller, since I came across a bulk purchase of these processors. The board features a 20MHz crystal.
- voltage (6-12v) is applied to the Surface mounted DC Barrel Jack and fed through a resettable fuse and into a 5Vdc LDO.
- Unlike some Arduino boards i made it a point to have 5V available at every header. so for each header you will find 5vdc and ground encasing each header.
- 5v is fed to an onboard 3.3v regulator for the 433MHz Linx Technologies Reciever/Decoder. sorry i did not bring 3.3v out to a header. The Receiver also has 5 dedicated input Ports [A4:A0] to the pic.
- I am not a fan of parallel so Ports [D7;D0] are fed to an 8-bit Darlington Array which drives 8 Blue LEDs and the entire header on the far right hand side of the board. the LEDs can be disabled via Mosfet setting PortB.1 Low .
- Ports A5, and [E2:E0] are standard I/O's, However, the 4 pin surface mounted dip switch dertermines wether these I/O's are pulled up through a 10k resistor or not. Useful if you need some buttons for your project.
- I made ports [C2:C0] independent headers for the sole purpose of serial devices. i use the RFID module from parallax as well as the uOLED-128-G1 display on these headers. power,ground,signal... simple and Perfect !
- Up on top is a dedicated SPI bus for parts that require some major bit banging. the Winbond ISD series voice chips come to mind. RC5/SDO,RC4/SDI,RC3/SCK,and RB3/SS are available on this bus.
- Last but not least is the communications bus. Here you will find RC7/RX, RC6/TX, RB5, and RB4. This bus is used by the XBEE AEGIS Daughter board shown below.

I have modified my Melabs USB U2 Programmer for ICSP programming through the Mini-USB-B connector. Although not shown I have designed adapter boards that will connect to the Mini-USB and the U2 programmer via the 10 pin ISCP header.

And there you have it.

5071 5070 5072 5074 5075

cncmachineguy
- 12th January 2011, 00:48
I like it, seems well thought out and nice clean execution!!