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General Category => Discussion - Software => Topic started by: Slava on December 21, 2020, 12:52:45 PM

Title: An issue with libMPSSE while accessing both I2C and GPIO on the same FT4232 port
Post by: Slava on December 21, 2020, 12:52:45 PM
Hello,

I have got a HW design where I2C lines and a mux, which commutates the I2C lines to different devices (have the same address), are connected to the same FT4232H port (I2C - BDBUS0,1,2 and Mux - BDBUS5,6,7). I'm trying to use libMPSSE 0.6 to access this device. In the begging of the code I call FT_WriteGPIO to choose the mux direction and then I2C_DeviceWrite to send I2C transaction. Unfortunately, in the first clocks of I2C transaction at least one of the ports connected to the mux changes, so the mux sends the rest of the transaction to another line. Is there any limitation to use I2C and GPIO of the same port simultaneously?

Thanks,
Slava