PIC18F46K80 I2C - P82B715 to MCP9808 Temp sensor

[georgedd]

I have a 82B715 I2C bus extender connected to a PIC18F46K80 which in turn is connected via another 82B715 to Microchip MCP8908 Digital Temperature Sensor.
See attachment " PIC18F46K80 I2C - P82B715 to MCP9808 Temp sensor.jpg"

I am using Flowcode v5.5.2.1 with the I2C component set up as: I2C1 (Hardware) at 100kHz with both Enable Slew Rate Control and Enable SMBus Inputs enabled.

The problem I am experiencing is that typically the I2C does not "initialize" and I received a "1" back from the MIC2_Transmit_Byte macro. Resetting the EB006-00-7 Multiprogrammer via the reset switch does not help, only a power off and then On will work. Once the "initialization "/ "start up" is successful there is typically no further problem with the I2C communications.

I have a delay before MI2C_Init() is called of around 4 seconds and around 500ms after. If Enable SMBus Inputs selection is NOT enabled it is extremely difficult to get the I2C to work. All other functions of the PIC18F46K80 appear to work fine.

Please help.

Regards,
George.