TMS320F28377S: Flash wait state for flash write

R H

Prodigy 50 points

Part Number: TMS320F28377S

Hi,

For configurations: XTAL= 10 MHz, PLL SYSCLK = 50 MHz

By using RWAIT = 3, Flash erase and write for FW update is working ok. But datasheet suggests below:

With RWAIT as 0, CPU is crashing.

Please help in understanding this.

over 4 years ago

0 Nirav Ginwala over 4 years ago

TI__Genius 15385 points

Hi,

What do you mean by CPU is crashing? Is the PLL locked at 50Mhz, what are your PLL settings?

Can you please share the fail information?

Best Regards,

Nirav

0 R H over 4 years ago in reply to Nirav Ginwala

Prodigy 50 points

Hi,

PLL settings for 50MHz: InitSysPll(XTAL_OSC,IMULT_10,FMULT_0,PLLCLK_BY_2); | XTAL = 10 MHz | Also verified using pin clkout

Getting below error when: Flash0CtrlRegs.FRDCNTL.bit.RWAIT = 0;

No source available for "_system_post_cinit() at C:/Users/filepath......out:{3} 0x3fe493{4}"

7625 ESTOP0 (Diassembly)

But works ok with: Flash0CtrlRegs.FRDCNTL.bit.RWAIT = 0x3;

Please guide.

0 Nirav Ginwala over 4 years ago in reply to R H

TI__Genius 15385 points

Hi,

When do you get this error? Did you step through your code to see? Also, when you change the RWAIT, are you executing the code from Flash or RAM?

Best Regards,

Nirav

0 R H over 4 years ago in reply to Nirav Ginwala

Prodigy 50 points

Hi,

Nirav Ginwala said:
are you executing the code from Flash or RAM?

.TI.ramfunc : {} LOAD = FLASHK,
RUN = RAMLS0 | RAMLS1 | RAMLS2 |RAMLS3,
LOAD_START(_RamfuncsLoadStart),
LOAD_SIZE(_RamfuncsLoadSize),
LOAD_END(_RamfuncsLoadEnd),
RUN_START(_RamfuncsRunStart),
RUN_SIZE(_RamfuncsRunSize),
RUN_END(_RamfuncsRunEnd),
PAGE = 0, ALIGN(4)

the above is defined in linker. We are loading from flash and run from RAM:

memcpy(&RamfuncsRunStart, &RamfuncsLoadStart, (size_t)&RamfuncsLoadSize);

Nirav Ginwala said:
When do you get this error?

during FW update. We get data serially and copy it to flash using Flash API.

Nirav Ginwala said:
Also, when you change the RWAIT

Before running we keep to a fixed value(0 or 0x3). i.e not changed at run time.

0 R H over 4 years ago in reply to R H

Prodigy 50 points

Hi,

Nirav Ginwala said:
are you executing the code from Flash or RAM?

the above is defined in linker. We are loading from flash and run from RAM:

memcpy(&RamfuncsRunStart, &RamfuncsLoadStart, (size_t)&RamfuncsLoadSize);

Nirav Ginwala said:
When do you get this error?

during FW update. We get data serially and copy it to flash using Flash API.

Nirav Ginwala said:
Also, when you change the RWAIT

Before running we keep to a fixed value(0 or 0x3). i.e not changed at run time.

One change we did was:

-l F021_API_F2837xD_FPU32.lib

adding Flash API library to RAM in linker. By this RWAIT=0 is working and no crash observed.

But the flash copy was working with RWAIT=0x3 and without -l F021_API_F2837xD_FPU32.lib in linker, and Flash copy was working ok with active code section HEX file received serially.