I²C interfacing

gaara · Published in 2015-5-11 01:35:38

Edited by gaara at 2015-5-10 19:34

Hi all,

I'm trying to learn about I2C interface on orange pi; because all is not clear for me.

I know there's

SDA (Serial Data Line)
SCL (Serial Clock Line)
+3.3V
GND

I know also that I2C is called asso TWI. So I have read the range datasheet, and I see this (image)

But: does SCK and SCL the same thing ?
In this case, can we plug 3 I²C differents devices ?

Thanks

Tyrannus · Published in 2015-5-11 02:19:26

I2C and TWI is the same

But: does SCK and SCL the same thing ?

No
SCL is the Clock from I2C/TWI, SCK is the Clock from SPI

In this case, can we plug 3 I²C differents devices

Yes ... with the (old) 7bit up to 112 devices. With same devices max 8 on one I2C Bus (the last three adressbits must be set over Jumper or Dip)

With the newer 10 bit I2C Bus up to 1136 devices

regards

gaara · Published in 2015-5-11 02:42:14

Edited by gaara at 2015-5-10 21:03

Ok thanks.
But where are the SCL bus in the Orange ?

The documentation is a little poor...
If ti's the same as RPi:

Correct ?

igorpec · Published in 2015-5-11 12:21:03

yes, correct. You can stick to Rpi's manual.

gaara · Published in 2015-5-11 16:38:05

Ok, thanks. I will try like this

dreadbit · Published in 2015-9-3 18:52:04

Well, if that semi-clear with pinout, what to do with that from programming side - on Raspbian on H3 CPU (Mini 2) device?
As I understand there shoud be some kernel support for that, but rasbperry docs calls it bcmXXX_i2c , and it will not work on H3 CPU, I bet.

I have some small OLED I2C display to play with.

I²C interfacing

This thread contains more resources