This pocket sized mp3 player is based on Microchip PIC16F877 and comes with both C and Assembly source code but the C code version has more features and stability. The mp3 player was designed to work with compact flash cards up to 100 gigabytes. For decoding it uses the VS1001K chip and for conversion it uses the built in DAC. The principle of operation is not very complicated, the PIC reads the CF card and once it finds a file it clocks the card 512 times per sector sending all the information one byte at a time to the decoder chip. The decoder gets a valid stream of data and sound comes out of the built in DAC. The project doesn’t have a display or a fancy menu, it’s just a plain simple mp3 player.
DIY Mp3 Player Based On PIC16F877: [link]
A teams of students from Colorado State University have designed and built a PIC-based circuit to control the flight of a blimp. You can control it manually by remote or let the zeppelin find it’s own path to a specific destination that is designated by an infrared beacon.
The remote control has a 20×4 LCD display which shows the commands and a 12 key keypad from which you can control take off, land, forward, reverse and steering commands. The zeppelin also has an altitude controller with ultrasonic sensors. This makes it go higher if it detects the ground too close or go lower if it’s altitude increases too much.
The thrust is given by two motors, each set at the end of a horizontal bar. A servo motor controls the angle of this bar and thus the direction of the thrust. There are four IR sensors each placed in the four cardinal points. These sensors serve the autonomous flight mode. The IR sensors output a low pulse when it “sees” the beacon so the zeppelin will follow the direction of the sensor which gives out the most pulses. The beacon is made with 16 IR LEDs driven by two 555 circuits.
The altitude control is been taking care of by a PIC16F84 designated IC2 in the schematics, steering is done by a PIC16F88, IC3, and all communicate with the control center a PIC16F874, IC4. Thrust motors are driven by SN754410, IC5 in the schematics. In the remote control you will find a PIC16F877P who takes care of all the RC functions, reading the keypad, displaying characters on the LCD, sending audio message to speaker and sending serial commands to the zeppelin.
Controlling the flight of a Zeppelin: [Link] – [Via]
The Digital thermometer was built by using the temperature sensor LM35DZ, PIC16F877 microcontroller and MAX232 IC. Temperature measurements can also be viewed on a computer program which can monitor the state of COM ports of a PC. Sample measurement data received through COM2 is being viewed on the SERIAL WATCHER program which is distributed freely on the internet.
Digital thermometer: [Link]
The circuit here described is a simple 4×5 keypad that can be used in particular with the PIC 16F877 microcontroller, for which it has been designed considering a supply of 5V, 16F877 I/O pins leakage current, the voltage level recognized as a high or low state while in TTL or ST mode, etc.. Since this circuit is quite simple, and the resistors’ value not critical, it should be suitable for other PICs and other microcontrollers, too.
PIC16F877 and 4×5 keypad: [Link]
This circuit is not a PIC programmer, but it can be easily interfaced with one of the many programmers you can find, allowing you not to remove the microcontroller from the board (in-system programming).
Compared to the version 1.1, connection also to LVP programmers is now supported; besides this characteristic, it is of course possible to work both with chips with the LVP bit set (just a switch need to be set) and with the LVP bit not set; it is of course possible to interface the board with traditional programmers (12 V on /MCLR), the most part, I would say.
PIC 16F877 / 16F874 Development Board: [Link]