Problem when doing a bulk erase using JTAG

Altera_Forum · ‎07-03-2008

Hello,

I am trying to bulk erase a EPM7512AETC144-10 using a 68HC09 microcontroller connected to the JTAG pins of the MAX7000. According to the SVF file, a bulk erase requires the following instructions:

!BULK ERASE

!

SIR 10 TDI (00A);

RUNTEST 1000 TCK;

!

So I implemented a function in C to match theses instructions:

int j=0;

short int IRData[10]={0,1,0,1,0,0,0,0,0,0}; // 1st 10 bits of 0x00A (least significant bits first)

///-----------Disable Interrupt------

# ifdef __HIWARE__

asm TPA;

asm PSHA;

asm SEI;

# else

# pragma asm

TPA

PSHA

SEI

# pragma endasm

# endif

PTD_PTD0 = 0; //TMS=0

for (j=0;j<100;j++)clock_Cycle(); //Run test idle for 1ms at least

PTD_PTD0 = 1; //TMS=1

clock_Cycle(); //Select DR Scan

clock_Cycle(); //Select IR Scan

PTD_PTD0 = 0; //TMS=0

clock_Cycle(); //Capture IR Scan

clock_Cycle(); //shift IR Scan

for (j=0;j<10;j++)

{

PTD_PTD2 = IRData[j]; //Shifting data bits

clock_Cycle();

}

PTD_PTD0 = 1; //TMS=1

clock_Cycle(); //EXIT IR

clock_Cycle(); //UPDATE IR

PTD_PTD0 = 0; //TMS=0

clock_Cycle(); //run test idle

///-----------Enable Interrupts------

# ifdef __HIWARE__

asm PULA;

asm TAP;

# else

# pragma asm

PULA

TAP

# pragma endasm

# endif

break;

However, when this function is called, the MAX7000 doesn't seem to be erased and is even still running. Does anybody see something wrong with this function? Or are there some instructions to perform before theses? I checked the waveforms for TMS and TDI and everything seems to be ok (See the attachment).

Thanks ,

Cyril

Altera_Forum · ‎07-03-2008

My recommendations:

1. Check the TDO output with the scope as well. It should be high-z in all TAP controller states except shift DR and shif IR. So you can see if you managed to move the TAP controller to the appropriate state.

2. There should be a TAP controller reset at the very beginning of your sequence

PTD_PTD0 = 1; //TMS=1

for (j=0;j<5;j++)clock_Cycle(); // test logic reset

PTD_PTD0 = 0; //TMS=0

clock_Cycle(); // test idle

PTD_PTD0 = 1; //TMS=1

...

Hope that helps,

Harald