Debug Connector - Silicon Laboratories EFR32xG21B User Manual

3.5 Debug Connector

The debug connector serves multiple purposes based on the "debug mode" setting which can be configured in Simplicity Studio. When
the debug mode is set to "Debug IN", the debug connector can be used to connect an external debugger to the EFR32 on the radio
board. When set to "Debug OUT", this connector allows the kit to be used as a debugger towards an external target. When set to "De-
bug MCU" (default), the connector is isolated from both the on-board debugger and the radio board target device.
Because this connector is electronically switched between the different operating modes, it can only be used when the board controller
is powered (i.e., J-Link USB cable connected). If debug access to the target device is required when the board controller is unpowered,
connect directly to the appropriate breakout pins.
The pinout of the connector follows that of the standard ARM Cortex Debug+ETM 19-pin connector. The pinout is described in detail
below. Even though the connector has support for both JTAG and ETM Trace, it does not necessarily mean that the kit or the on-board
target device supports this.
Note: The pinout matches the pinout of an ARM Cortex Debug+ETM connector, but these are not fully compatible because pin 7 is
physically removed from the Cortex Debug+ETM connector. Some cables have a small plug that prevent them from being used when
this pin is present. If this is the case, remove the plug or use a standard 2x10 1.27 mm straight cable instead.
Pin Number(s)
1
2 TMS / SDWIO / C2D
4 TCK / SWCLK / C2CK JTAG test clock, Serial Wire clock, or C2 clock
6
8
10 RESET / C2CKps
12
14
16
18
20
9
11, 13
3, 5, 15, 17, 19
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1
VTARGET
GND 3
GND 5
NC 7
Cable Detect 9
NC 11
NC 13
15
GND
GND 17
19
GND
Figure 3.4. Debug Connector
Table 3.2. Debug Connector Pin Descriptions
Function Description
VTARGET Target reference voltage. Used for shifting logical signal levels between target and
debugger.
JTAG test mode select, Serial Wire data, or C2 data
TDO/SWO JTAG test data out or Serial Wire Output
TDI / C2Dps JTAG test data in or C2D "pin sharing" function
Target device reset or C2CK "pin sharing" function
TRACECLK Not connected
TRACED0 PA03
TRACED1 Not connected
TRACED2 Not connected
TRACED3 Not connected
Cable detect Connect to ground
NC Not connected
GND Ground
UG428: EFR32xG21B 2.4 GHz 10 dBm Wireless Starter Kit User's Guide
2
TMS / SWDIO / C2D
4 TCK / SWCLK / C2CK
6 TDO / SWO
8 TDI / C2Dps
10 RESET / C2CKps
12 TRACECLK
14 TRACED0
16
TRACED1
18 TRACED2
20
TRACED3
Connectors
Rev. 1.0 | 11