Vareka, Bill wrote: > I need to be able to synchronize the clocks on several linux PC104s in our > system. For those that are on the pure Linux subnet I was planning on using > chrony but many of the nodes are connected via RtNet to a single master > gateway and I was wondering if anyone has thought of or tried to sync the > Linux times on various nodes of an RtNet network using the packet timestamp > info. We've got to do some high accuracy time stamping on each node I > already have a phase-lock-loop algorithm to sync between RTAI time and Linux > time by compensating for clock errors and drifts when I convert between tsc > clock counts and wall time. Thus if I could use RtNet to compare and
How complex is your PLL implementation? I'm still looking for some improvement of the clock synchronisation between RTnet nodes. Currently this is done on every master's sync packet without considering the (though low) jitter of packet transmission and especially reception (local IRQ jitter). As this is done quite frequently (depending on your TDMA cycle period), the calculation should preferably be simple. > compensate the tsc clocks this might yield very consistent times from each > node. Just wondering if anyone has walked this path before or has any > ideas. > I'm not aware of any application sync'ing the system time on the TDMA time. I guess most users (us included) stay in one time domain with their applications. Anyway, should no be more complex then doing the same with the local RTAI time. Jan
signature.asc
Description: OpenPGP digital signature
