Silicon Labs EFR32xG21
The Silicon Labs (SiLabs) EFR32xG21xxx series devices are Cortex-M33 based MCUs.
Tracing on EFR32MG21xxx series
This section describes how to get started with trace on the SiLabs EFR32MG21xxx MCUs. This section assumes that there is already a basic knowledge about trace in general (what is trace, what different implementations of trace are there, etc.). If this is not the case, we recommend to read Trace chapter in the J-Link User Manual (UM08001).
- The sample projects come with a pre-configured project file for Ozone that runs out-of-the box.
- The following sample project is designed to be used with J-Trace PRO for streaming trace, J-Link Plus for buffer tracing (TMC/ETB trace) and Ozone to demonstrate streaming trace.
- In order to rebuild the sample project, SEGGER Embedded Studio can be used.
- All examples are shipped with a compiled .JLinkScriptfile (.pex), should you need the original source, please get in touch with SEGGER directly via our support system: https://www.segger.com/ticket/.
- The EFR32MG21xxx device only support 1-bit tracing (1-pin trace). Therefore, overflows can happen when tracing this chip. The higher the MCU clock speed, the higher is the chance to get overflows. To accommodate this stalling mode is enabled per default which stops target execution when a overflow would happen. However keep in mind, that any kind of stalling mode will affect the real time behavior of your system. So do not use trace on this target device if you do not want your target to be halted temporarily on trace overflows.
Tracing on SiLabs EFR32MG21xxx/MGM21xxx (SiLabs Wireless Gecko xGM210P022)
In order to use trace on the ST EFR32MGxxx MCU devices, the following minimum requirements have to be met:
- J-Link software version V6.64c or later
- Ozone V3.10f or later (if streaming trace and / or the sample project from below shall be used)
- J-Trace PRO for Cortex-M HW version V1.0 or later for streaming trace
To rebuild the project our IDE Embedded Studio can be used. The recommended version to rebuild the projects is V6.30. But the examples are all prebuild and work out-of-the box with Ozone, so rebuilding is not necessary.
The project has been tested with the minimum requirements mentioned above and a SiLabs Wireless Gecko xGM210P022.
Example project: SiLabs_EFR32MG21_TracePins.zip
Reference trace signal quality
The following pictures show oscilloscope measurements of trace signals output by the "Tested Hardware" using the example project. All measurements have been performed using a Agilent InfiniiVision DSO7034B 350 MHz 2GSa/s oscilloscope and 1156A 1.5 GHz Active Probes. If your trace signals look similar on your trace hardware, chances are good that tracing will work out-of-the-box using the example project. More information about correct trace timing can be found at the following website.
Trace clock signal quality
The trace clock signal quality shows multiple trace clock cycles on the tested hardware as reference.
The rise time of a signal shows the time needed for a signal to rise from logical 0 to logical 1. For this the values at 10% and 90% of the expected voltage level get used as markers. The following picture shows such a measurement for the trace clock signal.
The setup time shows the relative setup time between a trace data signal and trace clock. The measurement markers are set at 50% of the expected voltage level respectively. The following picture shows such a measurement for the trace data signal 0 relative to the trace clock signal.