FreeRTOS includes pre-configured projects for software emulations of microcontroller cores using QEMU open source emulator

FreeRTOS now includes pre-configured projects that emulate real microcontroller (MCU) cores in software using the QEMU open source emulator. Running FreeRTOS in an emulator makes it easier to test applications using the actual binary code that will run on your MCU device, without having physical access to the MCU device. MCU emulations reduce development time by giving you access to enhanced debugging capabilities and the flexibility to run design experiments on multiple MCUs before you make the final MCU selection. This release includes a QEMU demo project for the Arm Cortex-M3 based MPS2+ FPGA. For more details, see FreeRTOS README.

Source:: Amazon AWS