nrf51822 Minew's Module is not recognized by NRF51DK

[fercholas]

Hi guys

I am trying to program a nrf51822 module but it is not recognized by the development kit.

These are the pins that I am using:

I can not see the module with NRFGo on Windows or on linux with Jlink console.

Any idea?

Thanks in advance!

[Martin]

Hi

I had a similiar problem. The cause was not enough current being supplied over USB (<=2.9V on DK, measured at VTG).

Try the following: Short circuit VDD over VTG to device.

This enabled me to programm all devices without any trouble. From my experience you need to have at least 2.95V to programm the NRF.

Best

Martin

[RichieJH]

My voltmeter says I'm outputting 2.86volts to my custom PCB through the nRF 52 DK and the DK picks it up fine.

[fercholas]

Hi Martin

Thanks for answering. I have tried with the connection of P20 pins 2 and 3 without results.

• P20 pin 4 for SWDIO
• P20 pin 5 for SWDCLK
• P20 pin 8 for a connection between Modules's ground and NRF51DK's ground.
• P20 2 and 3 shorted.

Without the pins 2 and 3 short I have these voltages:

• 2.86V at VDD pin.
• 2.89 V at VTG pin
• 2.86 V at VnRF pin

This is the Segger Jlink output on Ubuntu:

nicolas@nicolas:~$ sudo JLinkExe -device nRF51822 -speed auto -if swd
SEGGER J-Link Commander V5.12e (Compiled Apr 29 2016 15:06:32)
DLL version V5.12e, compiled Apr 29 2016 15:06:27

Connecting to J-Link via USB...O.K.
Firmware: J-Link OB-SAM3U128-V2-NordicSemi compiled Mar 15 2016 18:03:17
Hardware version: V1.00
S/N: 681325908
VTref = 3.300V


Type "connect" to establish a target connection, '?' for help
J-Link> connect
Device "NRF51822_XXAA" selected.
TotalIRLen = ?, IRPrint = 0x..000000000000000000000000


Found SWD-DP with ID 0x0BB11477
Found Cortex-M0 r0p0, Little endian.
FPUnit: 4 code (BP) slots and 0 literal slots
CoreSight components:
ROMTbl 0 @ F0000000
ROMTbl 0 [0]: F00FF000, CID: B105100D, PID: 000BB471 ROM Table
ROMTbl 1 @ E00FF000
ROMTbl 1 [0]: FFF0F000, CID: B105E00D, PID: 000BB008 SCS
ROMTbl 1 [1]: FFF02000, CID: B105E00D, PID: 000BB00A DWT
ROMTbl 1 [2]: FFF03000, CID: B105E00D, PID: 000BB00B FPB
ROMTbl 0 [1]: 00002000, CID: B105900D, PID: 000BB9A3 ???
Cortex-M0 identified.

This device corresponds to nrf51DK's chip. I can't see module's chip.

Thanks in advance!

[Martin]

Hi I experienced something like this with a custom board some while ago. The problem was another diode being between vdd on custom board which led to an additional drop of 0.15V which in course was then 2.7 on the SoC... Try to short an additional supply of 3V to VTG, disconnect P20 pin 2. This approach solved it for me. It's working ever since.