I2C Communication
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Hi I am designing an amplifier where I've used I2C to communicate with two control circuit PICs (pic18f819) and then those PICs are also communicating to an-other PIC (same) via serdata serclck. The pull up voltage is 3.9 on one side of the pull-up resistors and appears 2.5 on the other side on I2c line while on ser line 2.5 on serdata and 0v on serclck. The PCB used to communicate but suddenly it is not communicating now. Is it because of 2.5 voltage appearing on I2C OR 0v on serclock OR thses pull up voltages drops dont matter ? can some one help please. I'm not sure about 2.5v on I2C and also what voltages are necessary for serdata/serclcl line ? kd
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Hi I am designing an amplifier where I've used I2C to communicate with two control circuit PICs (pic18f819) and then those PICs are also communicating to an-other PIC (same) via serdata serclck. The pull up voltage is 3.9 on one side of the pull-up resistors and appears 2.5 on the other side on I2c line while on ser line 2.5 on serdata and 0v on serclck. The PCB used to communicate but suddenly it is not communicating now. Is it because of 2.5 voltage appearing on I2C OR 0v on serclock OR thses pull up voltages drops dont matter ? can some one help please. I'm not sure about 2.5v on I2C and also what voltages are necessary for serdata/serclcl line ? kd
I really don't think our expert C/C++ programmers can help you with what is clearly a hardware problem.
Software rusts. Simon Stephenson, ca 1994.
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Hi I am designing an amplifier where I've used I2C to communicate with two control circuit PICs (pic18f819) and then those PICs are also communicating to an-other PIC (same) via serdata serclck. The pull up voltage is 3.9 on one side of the pull-up resistors and appears 2.5 on the other side on I2c line while on ser line 2.5 on serdata and 0v on serclck. The PCB used to communicate but suddenly it is not communicating now. Is it because of 2.5 voltage appearing on I2C OR 0v on serclock OR thses pull up voltages drops dont matter ? can some one help please. I'm not sure about 2.5v on I2C and also what voltages are necessary for serdata/serclcl line ? kd
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Hi I am designing an amplifier where I've used I2C to communicate with two control circuit PICs (pic18f819) and then those PICs are also communicating to an-other PIC (same) via serdata serclck. The pull up voltage is 3.9 on one side of the pull-up resistors and appears 2.5 on the other side on I2c line while on ser line 2.5 on serdata and 0v on serclck. The PCB used to communicate but suddenly it is not communicating now. Is it because of 2.5 voltage appearing on I2C OR 0v on serclock OR thses pull up voltages drops dont matter ? can some one help please. I'm not sure about 2.5v on I2C and also what voltages are necessary for serdata/serclcl line ? kd
As others have stated you are in the wrong forum but anyway ..... if you are ever concerned about voltage levels in circuit you need to refer to the manufacturer's Data Sheet specifically the the Input Voltage thresholds. It will tell you the minimum voltage that is guaranteed to be recognised as a logic 1 and the maximum voltage that is acceptable as a logic 0. That should answer your question. Hope that helps :)
Ali