RTOS/AM4379: M3 held in reset

Part Number:AM4379

Tool/software: TI-RTOS

Hi everyone

I had a problem.

The hardware platform I use is AM437x_IDK

The software platform I use is CCS9.0 and RTOS -SDK

When I do simulation debugging，M3 Kernel has been unable to connect。

M3_wakeupSS_1: Error connecting to the target: (Error -1266 @ 0x0) Device is held in reset. Take the device out of reset, and retry the operation. (Emulation package 8.1.0.00005)

I want to know how A9 wakes up M3,Thanks!