PIC 12F/16F/18F quick start
From DP
Contents |
Features
- Huge selection of chips, many still in DIP packages
- One inexpensive device (PICkit/ICD, see eBay for clones) programs and debugs most PICs
- Previously famous for a generous sampling program (now dead)
Reference
Programmers, IDEs, compilers
IDE and compiler
- Microchip's IDE called MPLAB
- MPLABX is Microchip's new cross-platform IDE and compilers for Windows, Linux, and Mac
- Microchip's C18 Compiler for PIC 18F
- Microchip's C30 Compiler for PIC 24F/33F
We use Microchip's free demonstration compilers with MPLAB. The demo compilers have certain optimizations that expire after 60 days, but we don't use those anyway.
There are many third-party C, BASIC, and Pascal compilers too
- SDCC is an open source compiler for some PICs
Programmers
One inexpensive device (PICkit/ICD, see eBay for clones) programs and debugs most PICs
- PICkit
- ICD
- Build your own ICD clone
Bootloaders
PICs do not ship with a bootloader, but there are many that you can program yourself. After the bootloader is installed, a programmer is no longer needed for simple firmware updates.
- ds30 Loader serial bootloader for most PICs (GPL), our favorite
- Diolan USB HID bootloader for PIC18F (GPL), another favorite
Basic circuit
Power and reset
- Connect all the supply pins to power or ground. Put a 0.1uF decouple capacitor on each positive supply pin, and put it as close to the chip on your PCB as possible.
Reset
Two schematics: with and without MCLR diode
- Reset is MCLR/VPP (voltage programming) on PICs
- Connect a resistor from MCLR to the supply voltage for normal operation, use 10Kohms for 12/16/18, use 2Kohms for 24/30/33
- 12F/16F/18F - The programmer puts 12-13volts on MCLR to put the PIC in programming mode. Use a small diode between the supply voltage and resistor to protect the supply voltage from the 13volt programming voltage
- 24F/30F/33F - The programmer holds MCLR low and enters a key to start programming mode. No high voltage is used, no protection diode is needed.