Hello,

I have problem with connecting to the EFR32MG21A010F1024 device on my own custom board. The board consist(at this time) of the EFR32 MCU, the decoupling capacitors and nothing else. I am using the J-link software pack v6.48b and the J-Link PLUS hardware. I try to use the J-Flash utility and after running the Target/Connect command I obtain an error:


Connecting ...
- Connecting via USB to J-Link device 0
- J-Link firmware: J-Link V10 compiled Jul 23 2019 13:46:10
- Device "EFR32MG21AXXXF1024" selected.
- Found SW-DP with ID 0x6BA02477
- Scanning AP map to find all available APs
- AP[3]: Stopped AP scan as end of AP map has been reached
- AP[0]: AHB-AP (IDR: 0x84770001)
- AP[1]: APB-AP (IDR: 0x54770002)
- AP[2]: AHB-AP (IDR: 0x84770001)
- Iterating through AP map to find AHB-AP to use
- AP[0]: Skipped. Invalid implementer code read from CPUIDVal[31:24] = 0x00
- AP[1]: Skipped. Not an AHB-AP
- AP[2]: Skipped. Invalid implementer code read from CPUIDVal[31:24] = 0x00
- Found SW-DP with ID 0x6BA02477
- Scanning AP map to find all available APs
- AP[3]: Stopped AP scan as end of AP map has been reached
- AP[0]: AHB-AP (IDR: 0x84770001)
- AP[1]: APB-AP (IDR: 0x54770002)
- AP[2]: AHB-AP (IDR: 0x84770001)
- Iterating through AP map to find AHB-AP to use
- AP[0]: Skipped. Invalid implementer code read from CPUIDVal[31:24] = 0x00
- AP[1]: Skipped. Not an AHB-AP
- AP[2]: Skipped. Invalid implementer code read from CPUIDVal[31:24] = 0x00
- Target interface speed: 200 kHz (Auto)
- VTarget = 3.135V
- Found SW-DP with ID 0x6BA02477
- Scanning AP map to find all available APs
- AP[3]: Stopped AP scan as end of AP map has been reached
- AP[0]: AHB-AP (IDR: 0x84770001)
- AP[1]: APB-AP (IDR: 0x54770002)
- AP[2]: AHB-AP (IDR: 0x84770001)
- Iterating through AP map to find AHB-AP to use
- AP[0]: Skipped. Invalid implementer code read from CPUIDVal[31:24] = 0x00
- AP[1]: Skipped. Not an AHB-AP
- AP[2]: Skipped. Invalid implementer code read from CPUIDVal[31:24] = 0x00
- Found SW-DP with ID 0x6BA02477
- Scanning AP map to find all available APs
- AP[3]: Stopped AP scan as end of AP map has been reached
- AP[0]: AHB-AP (IDR: 0x84770001)
- AP[1]: APB-AP (IDR: 0x54770002)
- AP[2]: AHB-AP (IDR: 0x84770001)
- Iterating through AP map to find AHB-AP to use
- AP[0]: Skipped. Invalid implementer code read from CPUIDVal[31:24] = 0x00
- AP[1]: Skipped. Not an AHB-AP
- AP[2]: Skipped. Invalid implementer code read from CPUIDVal[31:24] = 0x00
- ERROR: Could not find core in Coresight setup
- ERROR: Failed to connect.
Could not establish a connection to target.


When I try to use the J-Link Commander I am also not able to connect to the EFR32 device and read the flash content. The commander window contain:

SEGGER J-Link Commander V6.48b (Compiled Aug 2 2019 10:19:19)

DLL version V6.48b, compiled Aug 2 2019 10:18:25

Connecting to J-Link via USB...O.K.
Firmware: J-Link V10 compiled Jul 23 2019 13:46:10
Hardware version: V10.10
S/N: 600113010
License(s): RDI, FlashBP, FlashDL, JFlash, GDB
VTref=3.145V


Type "connect" to establish a target connection, '?' for help
J-Link>usb 0
Disconnecting from J-Link...O.K.
Connecting to J-Link via USB...O.K.
Firmware: J-Link V10 compiled Jul 23 2019 13:46:10
Hardware version: V10.10
S/N: 600113010
License(s): RDI, FlashBP, FlashDL, JFlash, GDB
VTref=3.148V
J-Link>mem 0x0 200
Target connection not established yet but required for command.
Please specify device / core. <Default>: EFR32MG21AXXXF1024
Type '?' for selection dialog
Device>
Please specify target interface:
J) JTAG (Default)
S) SWD
T) cJTAG
TIF>s
Specify target interface speed [kHz]. <Default>: 4000 kHz
Speed>
Device "EFR32MG21AXXXF1024" selected.


Connecting to target via SWD
Found SW-DP with ID 0x6BA02477
Scanning AP map to find all available APs
AP[3]: Stopped AP scan as end of AP map has been reached
AP[0]: AHB-AP (IDR: 0x84770001)
AP[1]: APB-AP (IDR: 0x54770002)
AP[2]: AHB-AP (IDR: 0x84770001)
Iterating through AP map to find AHB-AP to use
AP[0]: Skipped. Invalid implementer code read from CPUIDVal[31:24] = 0x00
AP[1]: Skipped. Not an AHB-AP
AP[2]: Skipped. Invalid implementer code read from CPUIDVal[31:24] = 0x00
Found SW-DP with ID 0x6BA02477
Scanning AP map to find all available APs
AP[3]: Stopped AP scan as end of AP map has been reached
AP[0]: AHB-AP (IDR: 0x84770001)
AP[1]: APB-AP (IDR: 0x54770002)
AP[2]: AHB-AP (IDR: 0x84770001)
Iterating through AP map to find AHB-AP to use
AP[0]: Skipped. Invalid implementer code read from CPUIDVal[31:24] = 0x00
AP[1]: Skipped. Not an AHB-AP
AP[2]: Skipped. Invalid implementer code read from CPUIDVal[31:24] = 0x00

****** Error: Could not find core in Coresight setup
Found SW-DP with ID 0x6BA02477
Scanning AP map to find all available APs
AP[3]: Stopped AP scan as end of AP map has been reached
AP[0]: AHB-AP (IDR: 0x84770001)
AP[1]: APB-AP (IDR: 0x54770002)
AP[2]: AHB-AP (IDR: 0x84770001)
Iterating through AP map to find AHB-AP to use
AP[0]: Skipped. Invalid implementer code read from CPUIDVal[31:24] = 0x00
AP[1]: Skipped. Not an AHB-AP
AP[2]: Skipped. Invalid implementer code read from CPUIDVal[31:24] = 0x00
Found SW-DP with ID 0x6BA02477
Scanning AP map to find all available APs
AP[3]: Stopped AP scan as end of AP map has been reached
AP[0]: AHB-AP (IDR: 0x84770001)
AP[1]: APB-AP (IDR: 0x54770002)
AP[2]: AHB-AP (IDR: 0x84770001)
Iterating through AP map to find AHB-AP to use
AP[0]: Skipped. Invalid implementer code read from CPUIDVal[31:24] = 0x00
AP[1]: Skipped. Not an AHB-AP
AP[2]: Skipped. Invalid implementer code read from CPUIDVal[31:24] = 0x00
Cannot connect to target.
J-Link>

Where can be the problem with the connecting? The communication across the SWDIO and SWCLK works, because some AHB-AP's has been found...
Does the Segger software 6.48b ability to connect to the EFR32MG21A010F1024?

Thank you for your response!
Regards,

milanatik