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[apricot_star]

What can we do if a I2C bus shared by 2 devices interfering each other when transmitting the signal?

Urgent help needed! Thx!

 

[blueroomelectronics]

It's called I2C Multi Master and you have to write software for collision detection. If it's only 2 devices just set one as a Master, the other as Slave.

 

[Pommie]

The only way they can interfere is if you have two devices with the same address or your hardware is wrong. What are the two devices?

Mike.

 

[apricot_star]

One is real time clock the other is CO2 sensor which share the same I2c bus that connected to one of the I/O pin of the MCU.

The clock can work perfectly well when there is no CO2 sensor, if the Co2 is attached at the hardware then the clock start to have some errors.

 

[Pommie]

Which clock, which sensor, which processor?

A better description of your circuit/software would help. Chip numbers, bus speed, pullup values, hardware/bit banged. The more information you supply the more likely someone will figure out what is wrong.

If you are bit banging the I²C then have you implemented clock stretching?

Mike.

 

[apricot_star]

The clock is PCF8583 Philips RTC
The sensor is K30 Engine from sense air.
I am using PIC 18f2620, c language
Pull up resistor is 10K