Denso BHT-300B User Manual page 102

PING Echo Request Send Timing (SEND TYPE)
Two types of echo request send timings are available: TYPE 1 and TYPE 2.
TYPE 1
After sending an echo request,
echo request again. For TYPE 1, the relationship between the INTERVAL and TIMEOUT should be
"INTERVAL ≥ TIMEOUT."
TYPE 2
After sending an echo request, PING
that, PING waits for
TYPE 2, no relationship between the INTERVAL and TIMEOUT is required.
If PING receives an echo reply:
If a timeout occurs:
PING waits
waits for
the period specified by INTERVAL and
for the period specified by INTERVAL and then
an echo reply to be received or for timeout to occur. After
then sends
88
sends
an echo request again. For
an