Getting started

Tracer is a serial port monitor. You open a port, watch the data, and send data back. Every session is written to disk while it runs, so there is no record button to press.

Installing

Download Tracer for macOS or Windows from the home page.

Tracer is not signed with an Apple or Microsoft certificate yet, so your operating system will ask about it the first time you open it:

• macOS — open Tracer, let macOS refuse, then go to System Settings → Privacy & Security, scroll to the bottom, and click Open Anyway. On Sonoma and earlier you can right-click the app and choose Open instead.
• Windows — SmartScreen shows "Windows protected your PC". Click More info, then Run anyway.

This is only needed on first launch. Updates install normally.

Opening a port

1. Plug in your device.
2. Click the port chip in the toolbar and pick your device. USB devices appear and disappear from this list as you plug and unplug them.
3. Set the baud rate. If your device needs something other than 8-N-1, set the data bits, parity, and stop bits too.
4. Click Open session.

Output starts streaming immediately. An amber recording bar appears above the input box, showing that the session is being written to disk.

If your device is not in the list, check that its USB-to-serial driver is installed and that the cable carries data — some USB cables are charge-only.

Sending something back

Type in the input box below the log and press Enter.

By default Tracer appends a line ending to what you type. If your device is not responding, the line ending is the first thing to check — see Sending data.

Saving the session

While a session is open, it is being recorded to a folder under Auto Log/ in your vault, named after the port and the time.

Click Save in the recording bar to give the session a name and move it into your vault properly. If you never save it, it stays in Auto Log/ and you can still find it later.

See Vault and logging for how sessions are stored.

Unplugging

Unplugging a device does not end the session. Tracer identifies devices by their USB vendor, product, and serial number, and reconnects automatically when the same device comes back. This means a firmware flash or a reset does not cost you your session or your log.

Multiple ports

You can have up to four ports open at once. Each one gets its own tab in the session bar below the toolbar. Switch between them by clicking the tabs, or with ⌘[ and ⌘].