Tuesday, October 30, 2012

AVR Atmega 74HC595 library 01

74HC595 is a 8-bit serial-in, serial or parallel-out shift register.

74HC595 ics are usefull to expand output ports of a micro.
This library implements a way to setup 74HC595 pins.

This library is inspired on bildr 74hc595 library for arduino http://bildr.org/2011/08/74hc595-breakout-arduino/.
Setup parameters in l74hc595.h
This library was developed on Eclipse, built with avr-gcc on Atmega8 @ 1MHz.


  • read risk disclaimer
  • excuse my bad english


  1. Hi David! thanks for you library! It was really helpful, but I've a little questions, in this par #define l74hc595_setregon(regindex) l74hc595_setreg(regindex, 1); How call it? What type of Technic is it? And congratulations for this! Best Wishes from México!

    1. Hello, thank you for your feedback!. You can use that define as a function, passing the register you what to turn on as a uint16_t variable. Something like this should do the job l74hc595_setregon(regindex). As example l74hc595_setregon(1) will turn on register output pin 2. I'm sorry but i do not understaind what you mean with Technic.

    2. Sorry for my bad English!, I try to say what type of method is it, But now I understood and I start to read a good sources for code C special for macros and define concept. Thanks again! Best regards!!