LPC8N04 EEPROM write over 4kB result chip locked

[kenchong]

Dear sir, 

   I have written some wrong code on written around 8kB data to the EEPROM from zero offset. Now Jlink show error below:

VTarget = 3.345V
- Found SW-DP with ID 0x0BC11477
- Unknown DP version. Assuming DPv0
- Scanning AP map to find all available APs
- AP[1]: Stopped AP scan as end of AP map has been reached
- AP[0]: AHB-AP (IDR: 0x04770031)
- Iterating through AP map to find AHB-AP to use
- AP[0]: Skipped. Could not read CPUID register
- ERROR: Could not find core in Coresight setup
- ERROR: Failed to connect.

anyway i can recovery the chip? Thanks

Best Regards,
Ken

[kenchong]

um... i have check the datasheet in detail but didn't find and topic related to this issue...

[frank_m]

Have you tried a mass erase with the GUI Flash tool that comes with MCUxpresso ?

You probably need the "Reset on connection" option.

[kenchong]

I try the GUI tool you show me , however both Jlink and MCUxpresso CMSIS-DAP are not working now, by the way, i try a hundred time connect with jflash and it's success connected and download once, but it's just not recognise again after reset the power and just keep show error while determining coresight soc version.

 

 

 

[frank_m]

Did you try to enable the "Rest on connection" checkbutton ?

Or try the MCU reset button on your develeompent board during the process ?

I do not have such a board, and cannot try myself.

[gusarambula]

Hello Ken,

One alternative may be using a tool like Flash Magic Tool (link below) which does support the LPC8N04 to connect to the board using ISP mode and erase the EEPROM.

https://www.flashmagictool.com/

I hope that this helps!

Regards,
Gustavo

[frank_m]

As you might have realized, this MCU has only 4kByte of EEPROM.

A chip lockup usually happens because of a fault exception happens inside a fault exception handler. Thus, the core locks up to prevent random actions and possible damage. This is usually resolved by a power cycle.

If a debugger-connect under reset does not work, you might need to get the MCU into system mode, i.e. start into the ROM bootloader, and do a mass erase.

I don't work with the LPC8, but the exact requirements for this procedure should be documented in the user manuals and/or application notes.