Add distributed clock - Githubissues

CendreQuasar540 commented 1 year ago

Add method/class to enforce clock synchronization between master and slave during initialization process.

jimy-byerley commented 1 year ago

The clock implementation is now precise at ~50µs

this is huge according to the ETG specifications, so improvements should be made
yet this is better than nothing

We will try to merge it in the master branch, and see what to improve afterward

improvements to investigate:

[ ] better control of the ethercat frame sending (currently flushing a bufferized send, but it does not guarantee all PDUs will be in the same frame)
[ ] realtime kernel patch
[ ] different ethernet adapters
[ ] measure the time regularity of tokio

jimy-byerley commented 1 year ago

Some of our problems are coming from the tokio timers tokio::time::Interval, according to this issue, their implementation is not precise below 1ms, and we need 1µs Let's use tokio-timerfd instead, experimentation shows that it is precise at least at 10µs

before:

after:

jimy-byerley / etherage

Add distributed clock #7