[FAQ] MCU-PLUS-SDK-AM243X: How-to test FSI external 1-device loopback on AM243x LP or EVM

AM243x LP

Software

• In CCS import "fsi_loopback_polling_am243x-lp_r5fss0-0_nortos_ti-arm-clang"
• Only modification is to comment out or disable internal loopback inside "fsi_loopback_polling.c" as shown below

    /* disable loopback */
    status = FSI_disableRxInternalLoopback(rxBaseAddr);
    DebugP_assert(status == SystemP_SUCCESS);

Hardware

• From AM243x LaunchPad Development Kit User's Guide (Rev. F) (ti.com) we have:
• Connect jumper cables between
  • J5.1 TX0_CLK -> J5.2 RX0_CLK
  • J5.5 TX0_D0 -> J5.6 RX0_D
• Rebuild and rerun FSI loopback test

AM243x EVM

Software

• In CCS import "fsi_loopback_polling_am243x-evm_r5fss0-0_nortos_ti-arm-clang"
• Comment out or disable internal loopback inside "fsi_loopback_polling.c" as shown below

    /* disable loopback */
    status = FSI_disableRxInternalLoopback(rxBaseAddr);
    DebugP_assert(status == SystemP_SUCCESS);

• I2C configuration to change MUX to select J5/J7 (FSI header) instead of HSE

• Sysconfig changes: Add I2C module with instance "I2C1" 

• Add I2C IO configuration in project. Could be added inside "fsi_loopback_polling.c"

Hardware

• From AM64x / AM243x Evaluation Module User's Guide (Rev. A) we have:

However, Rev C boards use J7 instead of J5 

• Connect jumper cables between. If Rev C then it is J7 

  • J7.1 TX0_CLK -> J7.2 RX0_CLK
    J7.5 RX0_D0 -> J7.6 TX0_D0

• Rebuild and rerun FSI loopback test