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Welcome to the PICEBS2 wiki

PICEBS2 (hardware details) is the name of a small embedded computer board targeted at teaching embedded systems programming. As its name suggests, it is the second iteration of a successful family of Microchip PIC board, this time with the objective to realize an all-in-one system (the debugger PICKIT3 is included on board).

Please note that, as a student, you can loan a board for free during your studies to work at home ;-) Just ask the laboratory responsible Pascal Sartoretti (sap) for the procedure to follow.


We, the PICEBS2 team, provide a comprehensive solution for

  • Practical work for HEI course Information systems given in second year.
  • All kind of project featuring a small-sized micro-controller.

What can be done with the PICEBS2?

The board is powerful enough to run applications with:

  • LCD and touch screen interface
  • Serial port usage (UART)
  • CAN interface
  • ...

To program this board, you do not require an external programming probe, as it already includes a PICKIT3 system for programming and debugging. All you need is an USB port and the free MPLAB-X IDE.


(hardware details).

Here is a list of the main PICEBS2's characteristics:

  • CPU PIC18F87K22
    • High range PIC18 family with 128kB Flash & 4kB RAM
    • RTC
    • 12 bits ADC
    • 11 timers
    • UART, SPI, I2C
    • ...
  • Onboard PICKIT3 debugger
    • Compatible with MPLABX
    • Can be used standalone or turned off
  • LCD Display
    • 320x240, 265k colors
    • Backlight
    • Resistive touch screen
  • Networking and communication
    • CAN bus
    • RS232
    • PS2 keyboard
    • Olimex UEXT
  • Development
    • All CPU pins are available on a connector
    • Standard HES-SO//Valais 26 pin header on board


Tips & tricks

  • CPU speed control
// to work at maximum CPU speed (64MHz) insert following code at start.
   PLLEN = 1;            // activate PLL x4
   OSCCON = 0b01110000;  // for 64MHz cpu clock (default is 8MHz)
// Caution -> the PLL needs up to 2 [ms] to start !
// Wait a moment if needed with: __delay_ms(2);
  • Change one bit on a port
// to change one bit on a port, use LATx and not PORTx
   LATH2 = 1;            // turn led on for example
  • Interrupt on change on PORTB (RB4-RB7)
// to clear the interrupt flag you have to read the PORTB
   PORTB;               // clear the latch change on PORTB
   RBIF = 0;            // clear the interrupt itself
  • Reduce current consumption
// To reduce consumption at minimum, do at least
   LCD_PowerOff();  // turn all LCD parts off
   UART_PowerOff(); // turn UART driver off
   Can_PowerOff();  // turn off MCP2515 chipset
// And define unused GPIOs as output
   TRISB5 = 0;      // for example
// You can measure (between white and yellow test points) about 630 uA after a SLEEP();
  • Link in low address range (download time reduced)
   - To reduce the time to download, you need to write a linker special command
      In the "XC8 linker" - "Extra Linker Option" write the following line:
      "-L-ACODE=0x0-0x10000 -L-AMEDIUMCONST=0x0-0x10000"
   - Another solution is to have an interrupt routine (even if nothing in)
   The full program needs to be smaller than 50% of CPU Flash memory.

Bugs, issues, questions and comments

Feel free to contact the PICEBS2 team if you encounter a problem. Do not forget to have a look at the Tips & tricks section.

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