* Some fun shots of TinyMatrix in the wild. LED module is piggybacked directly on top of the microcontroller. This circuit will run off a CR2032 coin cell for days. The middle 16 pins of the ATtiny4313 are GPIO, and will accomodate any DIP-package LED module. I'm using a 12-pin Lite-ON LTP-747C. LTP-757 family is also supported.Other LED products may require source code adjustments. ![]() Source code: (see TinyMatrix.zip at bottom of page) Hex file is ~2000 bytes, leaving ~2000 free for additional images and animation code. One static 5x7 graphic occupies 5 bytes of progmem. Microcontroller runs at 4mhz, internal oscillator. Multiplex timing is handled by hardware interrupts, producing a very stable display. LED refresh: line rate = 390hz. Divide by 5 lines/frame = frame rate of 78hz. *update - Special thanks to Craig Lindley for providing a code update to display custom text messages. See TinyMatrixScroll.zip at bottom of page. Schematic: ![]() Assembly: No ISP connections are provided. Flash the chip first using a seperate programmer board. Trim in half all microcontroller pins except Vcc & Gnd. Solder the power wires and pushbutton to the microcontroller, dead-bug style. ![]() Now piggyback the LED module, and solder to the 12 middle pins. ![]() Solder coin cell holder to power wires, which double as a necklace. Press the button to cycle thru different patterns. Remove battery to conserve power. Patterns: SKULL HEART TREE DIAMOND CUP STAR BLOSSOM NUKE FOX INVADER 1 2 3 4 Animations: CHECKERBOARD (test-pattern) PSY-TUNNEL HEARTBEAT RAIN FIRE To-Do: Sleep mode (aka auto-off) Add more patterns Add code to support other LED modules ![]() ![]() ![]() ![]() |