RD9Z1-638-4Li (MM9Z1_638 ref dsn) - programmed once, stopped responding

[dsamarin]

Hello,

We bought a RD9Z1-638-4Li to begin testing the functionality of the MM9Z1_638 chip. We are using a PE Micro Multilink Universal to program/debug.

I wanted to create a small "hello world" program by toggling PTA7:

PTA_PTA7 = ~PTA_PTA7;

I took pieces of code from the reference design code to try and get this program built quickly. Here is the relevant parts of the program:

#pragma c99 on

#include <stdio.h>

#include "derivative.h" /* include peripheral declarations */

#define EVER               (;;)

#define DO_NOTHING         {;}

/* FUNCTIONS FROM REFERENCE DESIGN CODE */

void SYS_Init(void);

void CPMUStartup(void);

void D2DInit(char);

/* END FUNCTIONS FROM REF DES CODE */

int main(void) {

  SYS_Init();

  CPMUStartup();

  D2DInit(1);

  DDRA = 0b10000000; // PA7 output

  while(1){

    __RESET_WATCHDOG();  /* feeds the dog */

    PTA_PTA7 = ~PTA_PTA7;

  }

  return 0;

}

After main() I have the function definitions for SYS_Init, CPMUStartup, and D2DInit, all pulled from the reference code.

THEN, I used the PE Micro to program the first time. PTA7 was not toggling, so I tried messing with other registers, and reprogramming. THIS time, the PE Micro could not detect the processor!

First I see "Device is secure. Erase to unsecure?" I hit yes.

Then I see the Power Cycle Dialog, saying "Target MCU is not responding." It asks to toggle power to get the debugger to see the chip. I follow orders and hit OK.

Then I see the "Erase to unsecure?" message again. I hit yes.

Then the P&E Connection Assistant comes up. Retry, still cannot connect to the chip.

Things I've tried/observed:

* Change BDM frequency and delay, none of that changes behavior.

* The Reset pin on the BDM1 header is toggling. It goes low for 45 usec, 330 msec high. Does this mean the chip is in some sort of pseudo-stop mode? This happens without the PE Micro connected.

* Updated PE Micro drivers.

* Went to a new PC, setup the environment, wrote another program, and tried "downloading" to the chip again. Still can't connect.

How can I get back to being able to download to the chip, and how can I prevent this lockout from happening again?

Thanks in advance for any help!

[iggi]

Hi Daniel,

please see this thread:

"Device is secure. Erase to unsecure?" error message comes up when I try to program MM9Z1J638 with P...

Either you should disconnect RESET_A line from RESET during programming, or disable analog watchdog.

Hope it helps.

Regards,

iggi

[karenbeaty]

Hi iggi,

I'm working with Daniel on this project. I tried the following and was unable to connect to the MM9Z1J638 with the PEmicro:

• disabling the analog watchdog by inserting the line B_WD_CTL = 0x00; before Sys_Init() in main
• tying a 470nF capacitor between RESET and GND to disable RESET
• disconnecting RESET from the circuit by bending the pin backwards, so that it no longer connected to the PEmicro Multilink

What would you recommend trying?

Thanks,

Karen

[iggi]

Hi Karen,

The most probably the device is secured. Did you try PEMicro's Unsecure12 tool?

I hope the device is not damaged. Check if it's getting hot.

I doubt the problem is related to PE's Multilink Universal programmer. Unfortunately, don't have that RD board on my desk to test it :-(

Regards,

iggi

[karenbeaty]

Hi iggi,

Updating the drivers for the PE Micro (and using the capacitor) fixed the problem. Thanks for all of your help!

Best,

Karen