[FAQ] SK-AM62: How to enable SoC_I2C2 on the User Expansion Connector (J3)

ROOT CAUSE:

• SoC_I2C2_SCL and SoC_I2C2_SDA lines are fed into the I2C Switch named as TCA9543APWR. 
  
  
• This is shown below in the attached schematics.
  
  
• There are two channels, the first one leading to EXP_I2C2_SCL, EXP_I2C2_SDA lines and the second one leading to CSI_I2C2_SCL, CSI_I2C2_SDA lines.
  
  
• So it is clear that we need to enable the channel 0 in order to access the EXP_I2C SCL and SDA lines.
  
  
• This can be easily achieved through software code.

Setup Environment:

• Board SK-AM62B-P1: https://www.ti.com/tool/SK-AM62B-P1#order-start-development
  
  
• SoC Initialization via SBL: https://software-dl.ti.com/mcu-plus-sdk/esd/AM62X/08_06_00_18/exports/docs/api_guide_am62x/EVM_SETUP_PAGE.html#EVM_FLASH_SOC_INIT  
  
  
• MCU PLUS SDK AM62x: https://www.ti.com/tool/download/MCU-PLUS-SDK-AM62X/08.06.00.18
  
  
  

Relevant Documents:

• TCA9543APWR Datasheet: https://www.ti.com/lit/ds/symlink/tca9543a.pdf?ts=1706863075743&ref_url=https%253A%252F%252Fwww.google.com%252F
  
  
  

Code Setup:

• I have attached the code file below, which one can download and run it straight away to see the results.
  
  
• But anyways here is a walkthrough of what is happening in the implementation.
  
  
  
  
• Firstly we are probing to see if I2C Switch is detected.
  
  
• Now we simply write 1 to the channel 0 as this will enable the channel 0. NOTE: If you want to enable channel 1 you need to write the value 2 to I2C Switch at 0x71.
  
  
  
  
• Once the value 1 is written to the I2C Switch at 0x71, now you can access the pin number 3 (EXP_I2C2_SDA) and 5 (EXP_I2C2_SCL) of User Expansion Connector (J3).
  
  
  

Code File:

i2c_read_am62x-sk_m4fss0-0_nortos_ti-arm-clang.zip