athrill

Athrill is a CPU emulator. Athrill was developed to easily execute and debug embedded programs on virtual microcomputer. You can evaluate bare metal programs or embedded control programs running on real-time OS.

Athrill started in the TOPPERS project with the V850. Version 3 (athrill3, from v3.0.0) is a CPU-independent core in C++, with one repository per target; the C generation ends with v1.2.1. Athrill supports four instruction sets:

Target repository	Instruction set	What runs on it
athrill-target-v850e2m	V850E2M	TOPPERS real-time OS programs
athrill-target-rh850f1x	RH850 (F1x)	programs for the RH850/F1x microcontrollers
athrill-target-riscv	RISC-V (RV64IMFC)	PX4 on the AIFoundry Erbium board, a board target in upstream PX4
athrill-target-stm32	Armv7-M (Cortex-M7)	the unmodified PX4 firmware of Pixhawk 4 (px4_fmu-v5), flown from QGroundControl

Athrill runs on a virtual clock (one clock per instruction, idle time skipped), so a run repeats exactly from the same inputs, and it can run in lockstep with the Hakoniwa co-simulation environment (--hakoniwa).

An optional block JIT (-DATHRILL_ENABLE_JIT=ON, built on sljit) gives the targets a common block builder and cache; a target translates its own instructions into it. The output stays bit-identical: PX4 runs about 1.8 times faster on the STM32 target (RTF 3.2 to 3.5 with tick skip) and 2.9 times faster on the RISC-V target (RTF 4.5). The targets' READMEs have the measurements.

Command-line options, memory maps, and core device parameters are described in the configuration reference.

Table of Contents

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• Requirements
• Install
• License

Requirements

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Athrill requires the following to run:

• OS
  • macOS (arm64)
  • Linux (x64, arm64)
  • Windows 11 (x64, Visual Studio 2022)
• Build tools
  • CMake 3.16 or later
  • A C11 and C++17 compiler (AppleClang, GCC, Clang, or MSVC)

Athrill uses the following editors for source debugging:

• Editor
  • [Linux]
    • geany
  • [Windows]
    • Sakura Editor

Install

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This repository holds the CPU-independent core. The athrill3 executable is built with CMake from a target repository, which pulls in this core through cmake/AthrillCore.cmake. For the V850E2M target:

git clone https://github.com/toppers/athrill.git
git clone https://github.com/toppers/athrill-target-v850e2m.git
cmake -S athrill-target-v850e2m -B athrill-target-v850e2m/build -DCMAKE_BUILD_TYPE=Release
cmake --build athrill-target-v850e2m/build

The target finds this repository as the sibling ../athrill checkout. To use a checkout somewhere else, add -DATHRILL_SOURCE_DIR=<path to athrill> to the first cmake command.

Running athrill3 without arguments displays its usage:

Usage:athrill -m<memory config file> [OPTION]... <load_file>
-i                             : execute on the interaction mode. if -i is not set, execute on the background mode.
-r                             : execute on the remote mode. this option is valid on the interaction mode.
-t<timeout>                    : set program end time using <timeout> clocks. this option is valid on the background mode.
-m<memory config file>         : set athrill memory configuration. rom, ram region is configured on your system.

License

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Athrill is licensed under the TOPPERS License Agreement (http://www.toppers.jp/en/license.html).