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Real-Time Example on NUCLEO-L053R8
This example implements the "Periodic-Sporadic" application on the STM32 NUCLEO-L053R8 board (ARM Cortex-M0+). The example demonstrates various real-time preemption scenarios among active objects in the QK and QV kernels. The example requires a logic analyzer.
STM32 NUCLEO-L053R8
Logic analyzer trace after pressing the button (QK kernel)
Code Organization
examples\arm-cm\real-time_nucleo-l053r8
|
+---qk // preemptive QK kernel
| +---armclang // ARM/KEIL MDK with Compiler 6 (ARM/CLANG)
| | rt-qk.uvprojx // uVision project
|
+---qv-ms // cooperative QV kernel (multi-stage tasks)
| +---armclang // ARM/KEIL MDK with Compiler 6 (ARM/CLANG)
| | rt-qv-ms.uvprojx // uVision project
|
+---qv-tt // cooperative QV kernel (time-triggered)
| +---armclang // ARM/KEIL MDK with Compiler 6 (ARM/CLANG)
| | rt-qv-tt.uvprojx // uVision project
Features Demonstrated
The example QP application consists of 2 periodic threads (Active Objects) and two sporadic, lon-running threads (Active Objects). Additionally, the Time-Triggered (TT) version has a tt-schedulier thread.
-
directory
qk: preemptive run-to-completion QK kernel -
directory
qv-ms: cooperative run-to-completion QV kernel with multi-stage tasks -
directory
qv-tt: cooperative run-to-completion QV kernel with time-triggered tasks
Builing the Examples
ARM/KEIL MDK
- Open one of the provided KEIL uVision projects (e.g.,
rt-qk.uvprojx) in Keil uVision IDE. Build/Debug/Download to the board from the IDE.
Running the Examples
Setting up a Logic Analyzer
The NUCLEO-L053R8 needs to be conntected to a logic analyzer as shown in the picture below.
Connecting STM32 NUCLEO-L053R8 to a logic analyzer
The logic analyzer needs to be configured as follwos:
- sampling rate: several MHz (e.g., 24MHz)
- trigger: Sporadic (PC.13 on the NUCLEO-L053R8), falling edge
- pre-trigger capture ratio: 20%