Posts: 2
Joined: Fri Oct 10, 2014 1:50 pm

I2C control of PIC16F677

Fri Oct 10, 2014 1:58 pm

I am trying to use my raspberry to control a PIC16F677 chip with I2C. The board is a TylorEdge SmartNixie IN18 1361 ( ... 8/1361.pdf).

I have hooked up the SDA and SCL lines. I know the chip is getting 5v and ground. Also in series, I have hooked up a PCA95555. That board is a two chip i2c expansion (

When powered up. I can see the PCA95555 chip at 0x20 and 0x21, but not the PIC16F677. The address for the PIC16F677 should be 0x1E. The hookup is as follows:
Raspberry Pi TES1388 -DS2 TES1388 - U2 PCA95555
SDA (3) --> SDA - (A7) --> SDA (U2-1) --> SDA (9)
SCL (5) --> SCL - (A6) --> SCL (U2-2) --> SDL (10)

What am I missing?

User avatar
Posts: 2803
Joined: Sat Jan 05, 2013 7:28 pm
Contact: Website

Re: I2C control of PIC16F677

Fri Oct 10, 2014 5:37 pm

You need to write code for the PIC16F677 - it is a microcontroller, and needs software to be an I2C slave for whatever functionality you want, without writing the code for it, it will just sit there, and not respond to I2C. - home of EZasPi, RoboPi, Pi Rtc Dio and Pi Jumper @Mikronauts on Twitter
Advanced Robotics, I/O expansion and prototyping boards for the Raspberry Pi

Return to “Beginners”