Lisp Runs on a $1 ATtiny3216

In the continuing quest for interesting projects that would have once commanded an entire research department, but can now be done for a few dollars, David Johnson-Davies has come up with a way to run the high-level language uLisp —his version of Lisp written for microcontrollers — on an ATtiny3216. This relatively new microcontroller costs just over a dollar, but packs in some impressive specs, including a 32kB of flash memory and 2kB of RAM. This just so happens to match up with the ATmega328P that was previously the smallest MCU that could run this interpreter.

That being said, this new project is something of a testament to how amazing modern MCUs are, and the new circuit consists of breakout board for the ATtiny3216 and a second breakout for an FTDI chip. These are linked together on a small circuit board, along with an LED for on-board output. Once set up, the user enters Lisp programs into a serial monitor over USB, executing the code on the ATtiny chip.

Programs can be saved into EEPROM with the (save-image) command, then restored with (load-image). A variety of functionality is available such as analog inputs and outputs, as well as I2C interfacing, which could be quite useful when experimenting with a new component. For more on Johnson-Davies’ uLisp experimentation, check out his OLED usage monitor covered here.