nRF51 DK won't connect with nRF Toolbox

[PB]

Hello,

I'm wondering if my nRF DK51 is not broken as it behaves quite strange when trying to connect with a BLE Central (iOS and Android devices). For most of the part everything is ok (flashing, RTT, UART, BLE advertising) but when I try to connect on any of devices it immediately breaks the connection.

Initially I thought that it's an iOS thing since there's a few quirks when changing firmware and GATT for a device with the same MAC address. But the same issue persists on Android which IIRC relies less on caching of GATT.

When trying with ble_app_uartwith nRF5 SDK 11 example on Android logs show the following:

...
Connection state changed with new status: 0 and new state: 2 (CONNECTED)
Connected to [MAC]
Discovering Services...
gatt.discoverServices()
Discovering Services...
gatt.discoverServices()   //Yes, second time
[Callback] Connection state changed with status: 0 and new state: 0 (DISCONNECTED)
Connection lost
Connection state changed with new status: 0 and new state: 2 (CONNECTED)
Connected to [MAC]
Connection state changed with new status: 0 and new state: 2 (CONNECTED)
Connected to [MAC]      //Yes, second time again
Discovering Services...
gatt.discoverServices()
...                     //and so on

I started having issues while running my own custom firmware and initially thought that I was running out of RAM but after some debugging I came back to SDK examples and noticed that the behaviour is the same.

Is there a chance that my nRF51822 on the DK got damaged somehow and could behave in such way?

[FormerMember]

My first thought is that the chip is not damaged. There is a risk of ESD damage, but that doesn't happen very often.

If you test one of our examples, place a breakpoint in the error handler, and run the chip in debug mode? Will the error handler be "called"?

[FormerMember]

Okay, I see.

Yes, whether or not the nRF51822-QFAB has sufficient RAM depends on the application. When I compile ble_app_uart in SDK 12.2.0, it uses 4.34 kB RAM.

The minimum required RAM by S130 v.2.0.1 is 4.95 kB, and the ble_app_uart example in the SDK doesn't need to use more than 4.96 kB. So the ble_app_uart will fit in the QFAB version.

(Total flash: 108 kB (softdevice) + 13.23 kB = 121.23 kB)