CCS/TMS320F28377S: EnDat 22 for single core

Tool/software: Code Composer Studio

Hello everyone,

I´m struggeling with the operation of the EnDat 22 protocol with my own HW. I´m using the single core variant of the TMS320F28377. The Hardware configuration is the same as the IDDK design, using the SPIB with GPIO24-27, GPIO34 for TxEn and GPIO 6/7 for the Clk. The only difference is, that i have to invert the GPIO32 signal for powering the position sensor, because my supply enable is low active.

I´m trying to operate the HW with the PM_endat22BasicPosAcc_DelComp project SW. The code runs through the EnDat_Init() function and stays at the loop

while (endat22Data.dataReady != 1) {}

after

//Encoder Receive Reset - Command ERR

retval1 = PM_endat22_setupCommand (ENCODER_RECEIVE_RESET, 0xAA, 0x2222, 0); //data1=any; data2=any

PM_endat22_startOperation();

With the oscilloscope i only see the EnClk going low for some ns and back high staying there forever. The other lines SIMOB or SOMIB does nothing (staying low all the time).

What I´m doing wrong? Does the code only work for the dual core variant?

Many thanks for your help,

Florian