CCS/AM5728: The LED cannot blink used GPIO.

Part Number:AM5728

Tool/software: Code Composer Studio

Hi, everyone!

        we have custom board base on am5728 . on our custom board, we need blink the LED used GPIO before the linux start.  The LED never change, when we initialed the GPIO and set the GPIO value before linux start , but use the same code in the linux , it works well.  what else we should do in initial ? Could some one give me some advices, please?

The step of initial GPIO is: 

GPIO3_28_MUX_CFG = GPIO3_28_MUX_CFG | 0xE;

CM_L4PER_CLKCTRL = 3;

CM_L4PER_GPIO3_CLKCTRL = 1;

GPIO3_SYSCONFIG = GPIO3_SYSCONFIG | 2;

Delay(10);

GPIO3_CTRL = GPIO3_CTRL & (~1);

GPIO3_OE = GPIO3_OE & (~BIT28);

for(int i = 0; i < 5; i++)

{GPIO3_SETDATAOUT = GPIO3_SETDATAOUT | BIT28;

Delay(10000);

GPIO3_CLEARDATAOUT = GPIO3_CLEARDATAOUT | BIT28;

Delay(10000);

}

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