NRF52832 Booloader Problem

[cool__looc]

Hi All,

I'm using NRF52832 for our product. I test bootloader functionalities with development kit. The software system is also tested separately by directly programming to the device.

But the device will never connect after I flash the bootloader "examples/dfu/bootloader_secure_ble" from the sdk13. Even can not recover with "nrfjprog -f nrf52 --recover", it always shows the following message:

****** Error: Could not find core in Coresight setup
Found SW-DP with ID 0x2BA01477
Found SW-DP with ID 0x2BA01477
Could not power-up debug power domain.
Scanning AP map to find all available APs
AP[0]: Stopped AP scan as end of AP map has been reached
Iterating through AP map to find AHB-AP to use
Found SW-DP with ID 0x2BA01477
Found SW-DP with ID 0x2BA01477
Could not power-up debug power domain.
Scanning AP map to find all available APs
AP[0]: Stopped AP scan as end of AP map has been reached
Iterating through AP map to find AHB-AP to use
Cannot connect to target

The following is the schematics:

Is the bootloader brick the chip? What could be the problem?

To be short:

1. erase/flash softdevice and any program is ok;

2. whenever flash the bootloader then the device can no longer detect by jlink;

Thanks,

[Simonr]

Hi

First off, your schematics look good, so I think it's safe to say that this isn't a hardware issue. Can you show me the procedure of how you're flashing the bootloader onto your device? It might be that the device goes straight to bootloader mode when you flash it onto the chip. In that case, it should be advertising over BLE with the device name DfuTarg. Can you check if you're able to find it advertising? When the bootloader starts it will determine if it has a valid app based on the state of the settings page and a CRC check verifying the integrity of the application, so you'll need to perform a DFU to get the app into the system. 

Best regards,

Simon

[cool__looc]

Hi Simon,

Thanks for your reply. It turns out after flash the bootloader to the device then the nRst pin is low. After pull-up this pin the device can access again. But what could be the reason for this? I assume the bootloader will not configure this pin, is that right?

Thanks,