The PICAXE system is a powerful, low cost microcontroller programming system designed to simplify educational and hobbyist use of microcontrollers. PICAXE chips can be programmed in a graphical ‘flow-chart’ environment or in easy to understand BASIC.

PICAXE-20X2 microcontroller chip. Enhanced 20 pin microcontroller with individual pin control, 64MHz option and additional features including i2c/spi bus support.

• Pins: 20
• Memory (lines): 1000
• I/O Pins: 17
• Outputs/Inputs: 1-17 (Configurable)
• ADC (L=low): 0-8
• Data Memory: 128 +i2c+128 Scratch
• Based on the PIC PIC18F14K22

Memory (lines) = Approximate number of lines of program code the chip can hold.
Data Memory = Bytes of EEPROM memory on board. “128 (-Prog)” means 128 Bytes less the space needed for your program. 256+I2C means 256 Bytes + any external EEPROM space you add via the I2C interface).
Polled Interrupt = A process that automatically checks a pin in between each command to see if something has happened (very useful!)

Resources

• PICAXE Manual Part 1 – Getting Started (.pdf)
• PICAXE Manual Part 2 – BASIC Commands (.pdf)
• PICAXE Manual Part 3 – Interfacing Circuits (.pdf)
• Programming Editor (.exe)