Crate tag_cal 

tag-cal: put an IDLE tag in sensor-calibration mode and stream its raw samples until Ctrl-C.

Port of host/commandline/tag-calibrate.cc (built as tag-cal). Syncs the clock, starts calibration, then repeatedly fetches the calibration log and prints each sample as Raw:ax,ay,az,0,0,0,mx,my,mz (CRLF line ends), the format calibration front ends read. Ctrl-C ends the stream and the tag is stopped.

Exits 0 after streaming; 1 if the tag is not IDLE, or the attach, the first status read, the clock sync, the calibrate request or the final stop fails.

Usage: tag-cal [-d] [-b BUS:DEVICE]. The clap command name is tag-calibrate, the C++ name, so help and errors print that.

Hardware side effects

The attach resets the tag; SetRtc sets its clock from the host; Calibrate moves it into calibration mode, and Stop takes it out on the way out. The Ctrl-C handler is installed only after the attach, so a Ctrl-C during the attach kills the process; one after it, even before the stream starts, still ends with the stop. A tag left in calibration mode (a killed process or a failed stop) must be stopped with tag-stop. A tag family without a calibration mode refuses (BitTag, for example).

Structs

Cli 🔒

starts calibration mode

Statics

EXECUTE 🔒

Cleared by Ctrl-C to end the sample stream.

Functions

fail 🔒

Prints message to stderr and returns exit status 1.

main 🔒

Attaches, checks the tag is IDLE, syncs its clock, starts calibration, streams until Ctrl-C and stops the tag.

stream_samples 🔒

Streams the calibration log until Ctrl-C or a failed fetch, printing one Raw: line per sample. The firmware buffers samples between requests, so requests are 100 ms apart, qtcalibrate’s streaming interval. Floats print with two decimals, as the C++ sets std::fixed with precision 2; a missing sensor prints as zeros.