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PiPIC dataflow diagram for simple (power) switching and monitoring tasks. The i2c service writes data to 5 byte receiver buffer and sends data from 4 byte transmit buffer. The received bytes are interpreted in the command loop. This loop can copy values from time register, event status, I/O files or arbitrary file register location to the transmit buffer. The commands can set bits in GPIO, write byte to GPIO/TRISIO registers, and set event and time triggered commands. The timed task is executed when the count down goes to zero. If the event triggered tasks are enabled, the corresponding command is executed in the event loop. Initialization is done from configuration file in EEPROM. All this is done on a relatively inexpensive silicon PIC12F675 with 64 bytes of data memory, 128 bytes of EEPROM and 1024 words of program memory.