What is the OTP Address for Checking Flash ECC Error Logic?

Hi Pashan,

Please reference SPNA106A, which is the example initialization code for the Hercules family.

http://www.ti.com/mcu/docs/litabsmultiplefilelist.tsp?sectionId=96&tabId=1502&literatureNumber=spna106a&docCategoryId=1&familyId=1931

From the file sys_startup_recommended.c, you will see the following

#define flash1bitError (*(unsigned int *) 0xF00803F0)

#define flash2bitError (*(unsigned int *) 0xF00803F8)

Regards,
Eric

Hello Eric,

In the following link :

http://e2e.ti.com/support/microcontrollers/hercules/f/312/t/117842.aspx

it is mentioned that :

"For devices that does not support diagnostic mode there are reserved location within OTP which are delirabetely programmed to have single-bit and double bit errors , which could be used for failure checks."

Now, in the spnu516.pdf for RM42 device, I see the following section which indicates this device does have FLASH DIAGNOSTIC MODE as shown below :

So, does it also have OTP for Flash ECC Logic Check? But the previous mail from Pratip tells me different.

May be my understanding is wrong.

Please elaborate more between two mail's discrepancy.

Thank you.

Regards

Pashan

-------------------------------

4.6.2 Diagnostic Mode

Flash wrapper can be put in diagnostic mode to verify various logic. There are multiple diagnostic modes

supported by the wrapper. A specific diagnostic mode is selected via the DIAGMODE control bits in the

diagnostic control register (FDIAGCTRL).

-------------------------------------------

Hello Support,

I find the following in spna106a.zip -- sys_startup_recommended.c module :

#define flashBadECC     (*(unsigned int *)0x20080000)

Can you please tell me whether there is an intentional ECC Error created within the Flash Space while programming the Microcontroller usng nowFlash Tool?

Or, this is a predefined address location which will always have ECC error?

Thank you.

Regards

Pashan

Pashan,

This location is in the mirrored flash address space.  It is not programmed into main flash as an error.  This is the check which uses the diagnostic mode to corrupt ECC (through Mirrored Flash access). 

Please see the checkflashECC() function.  Diagnsotic mode 7 is a special mode which allows for creating of ECC errors through mirrored flash accesses (test purposes only). 

Also note, there is a bug in this section of code.  Please change the following line ('4' to 'A'):

910         flashWREG->FPAROVR = 0x00005A01;                                    // Select ECC diagnostic mode, single-bit to be corrupted

Regards,
Eric

void checkFlashECC(void)

{

/* Routine to check operation of ECC logic inside CPU for accesses to program flash */

volatile unsigned int flashread = 0;

flashWREG->FEDACCTRL1 = 0x000A060A; // Flash Module ECC Response enabled

flashWREG->FDIAGCTRL = 0x00050007; // Enable diagnostic mode and select diag mode 7

flashWREG->FPAROVR = 0x00005401; // Select ECC diagnostic mode, single-bit to be corrupted

flashWREG->FDIAGCTRL |= 0x01000000; // Set the trigger for the diagnostic mode

flashread = flashBadECC; // read a flash location from the mirrored memory map

flashWREG->FDIAGCTRL = 0x000A0007; // disable diagnostic mode

Eric,

Does the flashBadECC value has to be that FIXED Address or it can be anything within the Mirror Flash Address SPACE?

Thank you.

Regards

Pashan

Pashan,

No, this is not the only address that can be used as any address can be used in the mirrored space.  However, the address and corresponding programmed ECC value play a role.  This has already been worked out for proper use in the Diag mode = 7 example code by using the correct DAT_INV_PAR value (which may make an assumption that this flash locations ECC is erased to 0xff).  If you plan to change to a different address, just make sure that you are creating the desired errors in this diag mode.  Please reference the LS12xx TRM, SPNU515, section 5.6.2.  The steps are highlighted in section 5.6.2.6. You may also want to reference the Syndrome Table in section 5.3.3

http://www.ti.com/lit/ug/spnu515/spnu515.pdf

Regards,
Eric

Pashan,

Also note that the address 0x20080000 is out of range for the TMS570LS04x device so you will need to assign a new address for this test on that device.