TMS320F280025C: Can't run Delay_us function on RAM

Eric Chen

Intellectual 1960 points

Part Number: TMS320F280025C

Dear expert,

We are trying to run Delay_us() on RAM.

As I know this function is required to run on RAM.

After adding below pragma code, I saw that when I called DELAY_US() inside ISR running from Flash.

DELAY_US() still run on flash.

I have to also move ISR to run on RAM to make DELAY_US() run on RAM.

Is this a requirement moving ISR from Flash to RAM when calling RAM function inside?

May I grant your help for this?

# pragma CODE_SECTION (SysCtl_delay ,".TI.ramfunc")

#define DEVICE_DELAY_US(x) SysCtl_delay(((((long double)(x)) / (1000000.0L /  \
                              (long double)DEVICE_SYSCLK_FREQ)) - 9.0L) / 5.0L)

ISR run on Flash => But Delay_us can't run on RAM

Move ISR to RAM => Delay_us can run on RAM

.map

Best Regards,

Eric Chen

9 months ago

0 Vivek Singh 9 months ago

TI__Guru** 117051 points

Hi Eric,

Can you step into DEVICE_DELAY_US function and then check the PC in both case.

Regards,

Vivek Singh

0 Eric Chen 9 months ago in reply to Vivek Singh

TI__Intellectual 1960 points

Dear Vivek,

From my screenshot, I have already stepped into this function.

As you see this function is only math calculation without any otherelse.

# pragma CODE_SECTION (SysCtl_delay ,".TI.ramfunc")

#define DEVICE_DELAY_US(x) SysCtl_delay(((((long double)(x)) / (1000000.0L /  \
                              (long double)DEVICE_SYSCLK_FREQ)) - 9.0L) / 5.0L)

Below statement, DEVICE_DELAY_US function is already copied to RAM by pragma.

Case1. Step into one by one with ISR on RAM