trice

🅃🅁ace 🄸d's 🄲 🄴mbedded

Hi, I am Trice.

Trice User Manual

Log in (a) trice (S>G)

even inside ↯ interrupts in less than 1 µs❗

What is Trice?

Trice replaces printf or log in C code and gives you three main benefits:

• Speed - Fast enough to use inside interrupts
• Small Size - Uses less FLASH memory
• More Features - Extra options that help developers

Main Idea

Instead of storing log strings on your embedded device, Trice keeps them on your PC. This makes logging faster and uses less memory on your device.

- No version mismatch problems❗
+ The Trice ID List stores all log strings, so the
+ newest version can read logs from all older versions❗

Two Parts of Trice

1. C code macros - Works like printf but creates very fast trace and log code for your embedded device
2. Trice tool - Manages and displays the logs
   • Written in Go - works on all platforms that Go supports
   • You can also build your own tool to receive Trice packages, replace IDs with text, and display the output

• Read the Trice User Manual
• Current Status: Trice is ready to use!

When to Use Trice

Logging and Debugging

You can use Trice for printf debugging and as a logging system. The advantage is very short messages (no strings) for data transfer. Remember that the file til.json is needed to read all output from devices in the field for 10+ years.

• Optional: Add til.json as a compressed resource to your target image. You can use SRecord or provide a download link.

Data Compression

Trice looks like data compression (IDs instead of strings), which is useful for IoT devices, especially NB-IoT with very low data rates.

FLASH Memory Storage

Store Trice messages in FLASH memory for later analysis. A typical trice uses only 4 bytes, no matter how long the format string is.

Encryption

You can encrypt Trice transfer packets for security.

• Deliver firmware images with encrypted Trice output that only works with the right key and til.json
• XTEA encryption is available

Translation

Translate the til.json file into different languages. Change the language by changing the til.json file without changing the target binary.

Timing Analysis

Trice makes timing analysis easy on distributed embedded systems. It supports both host and target timestamps.

How Trice Works (UART Example)

This simplified diagram shows how Trice works. Read the detailed explanation here.

Data Transfer Options

Implemented Transfer Methods

• UART - Can connect to virtual UART over USB
• RTT - Works with J-Link and ST-Link
• TCP4 (TCP4 input and TCP4 output)
• UDP4 (UDP4 input)

Other Transfer Options

• Use a small separate microcontroller as a bridge from GPIO, I²C, SPI, CAN, LIN to UART
• Use FTDI chips like Adafruit FT232H Breakout for easy GPIO, I2C, and SPI access

Display Server

• Start trice ds in a console on your local PC or a remote PC. Then connect several trice tool instances using commands like trice log -p COM15 -ds
• This allows to see the Trice logs of several devices line-by-line intermixed in one terminal.

Documentation

• https://interrupt.memfault.com/blog/trice (slightly outdated)
• Trice User Manual (includes updated information from the interrupt blog)
• Check issues and discussions, including closed items
• Read the target source code, especially triceDefaultConfig.h
• View CLI options by running trice help -all in a terminal or reading the generated file trice-help-all.txt
• Refresh the checked-in CLI help documentation with go generate ./internal/args
• Look at and modify ./internal/emitter/lineTransformerANSI.go if needed (requires running go install ./cmd/trice/... afterwards)

Debugging with VS-Code and Clang

Debug a Trice project in Direct-Out Mode over SEGGER-RTT. (See Development Environment Setup for details.)

Trice Cache

You can use the -cache CLI switch with trice insert and trice clean commands. This only works when you create the .trice/cache folder in your home directory. (Trice Cache Details)

When to Use Cache

Use cache when you:

• Use trice i ... before compiling
• Use trice c ... after compiling
• Want to keep IDs out of your source code when working
• Want faster compilation

How Cache Works

The Trice cache saves copies of all files after processing them with trice i or trice c. This avoids inserting and removing IDs repeatedly. The copies are used to get the same results for files that have not been edited. Edited files are processed normally and the cache updates afterwards. File modification times do not change, so the build system does not reprocess unchanged files even when IDs are temporarily removed.

Important Note

Be careful when your build system also modifies source files!

For example, run an auto-formatter before the trice insert command.

Which Mode Should You Use?

• For development: Direct mode with SEGGER_RTT is recommended
• For most use cases: Deferred mode with TRICE_BUFFER == TRICE_RING_BUFFER (uses less RAM) in TRICE_MULTI_PACK_MODE (transfers less data)

Project Status

Trice is fully usable. There are no known bugs (see issues).

+ Please use v1.0, v1.1, or the main branch if you want to build from source.
- Do not use the "dev" branch right now (December 2025) - it may not work properly.

Future Plans

The documentation could be improved. We could add features like remote procedure calls. Or create a separate tlog tool written in C or Python (with AI help). This would allow logging on any platform, not just platforms supported by Go.

Structured Logging

Trice will soon support structured logging. Based on feedback from #531, there is now a specification draft. Please provide feedback before implementation starts.

Support the Project

• Trice takes a lot of my free time. I want to keep it MIT licensed in the future.
• If you make profit using Trice in your products, donations help convince my family to continue improving Trice.
• ⭐ Star this project! ☺

Become a Sponsor with your Github Account

OR

OR

Clone the Repository

git clone https://github.com/rokath/trice.git

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