Justification: Address Broadcast Gaps

Wednesday, February 25, 2026 | 10:52am
Attachment Size
5.2.1- Broadcast Gaps.docx 14.29 KB
You must be logged in to comment. Log in
2 comments

Al Thomason Member for 3 years 6 months

Discussion

For products which support multiple functions it is often difficult to meet a 50mS gap between messages.  This is recognized already in RV-C spec:

"01A-S-10 Message Gap :    A product with multiple functions or instances is allowed shorter gaps if necessary to comply with the reporting requirements of the status DGNs for its multiple devices. In no case may the gap be less than 5ms."

As written the proposal does not directly include acknowledgment of multi-function devices which may well need to have shorter message gaps;  present no different load to the CAN bus than multiple discreet products supporting the same combination of functions.   Can language be added to the new proposed 5.2.1 wording, in line with the above 01A-S-10 concept?

Martin Perlot Member for 7 months 2 weeks

This is currently addressed in the statement: "If this is not sufficient, a device may reduce the global gap below 50 ms only as far as necessary to accommodate all supported messages, with reasonable allowance for operational variability." 

This is intended to address complex devices that require more than 20 msgs/sec.  I'm open to any ideas for improvement in the wording.