PICBIT: A Scheme System for the PIC Microcontroller
Marc Feeley, Danny Dub� · 2003
This paper explains the design of the PICBIT R 4 RS Scheme system which speciflcally targets the PIC microcontroller family. The PIC is a popular inexpensive single-chip microcontroller for very compact embedded systems that has a ROM on the chip and a very small RAM. The main challenge is fltting the Scheme heap in only 2 kilobytes of RAM while still allowing useful applications to be run. PICBIT uses a novel compact (24 bit) object representation suited for such an environment and an optimizing compiler and bytecode interpreter that uses RAM frugally. Some experimental measurements are provided to assess the performance of the system.