2 number of retries, 3 number of time slots for random retry, 4 number of bytes transmitted before delay – Campbell Scientific RF400/RF410/RF415 Spread Spectrum Radio/Modem User Manual
Page 19: 5 sync timer setting
RF400 Series Spread Spectrum Data Radio/Modems
11
Retries”, “Time-slots for Random Retry”, and “Bytes Transmitted before
Delay” settings.
STANDARD RETRY LEVELS
Menu
Retry
Level
Maximum
Retries
Time-Slots for
Random Retry
Bytes Transmitted
Before Delay
1
None
0
0
65535
2
Low
3
2
1000
3
Medium
6
3
1000
4
High
10
5
1000
4.1.4.2 Number of Retries
This setting specifies the maximum number of times an RF400 will re-send a
packet failing to get an ACK response. The default setting is zero which
inactivates retries. The allowable range is 0 to 255. Entering a number greater
than zero activates retries. A receiving RF400 responds to the sending radio
with an ACK packet for every RF packet that it receives, addressed to it, that
has a valid CRC.
4.1.4.3 Number of Time Slots for Random Retry
This setting is active when the Number of Retries is greater than zero. It
specifies the number of 38 ms time slots to create among which to randomly
re-send a packet which has failed to get an ACK packet response. The
allowable range is 0 to 255.
If packets are failing because of periodic noise or signals, specifying more time
slots for random retries will improve the chances for successful retry packet
delivery. Increasing the number of time slots, however, results in longer
average retry delays which could lower data throughput.
4.1.4.4 Number of Bytes Transmitted before Delay
This feature prevents an RF400 Series radio which has lots of data to transfer
from tying up a network until it is finished. The range of settings is 1 to 65535.
The default value is 65535 (bytes). This setting forces an RF400 to pause long
enough, after sending the specified number of bytes, for another radio to send
some data.
4.1.4.5 Sync Timer Setting
This setting determines how often sent packets will include hop
synchronization information in the headers. The default setting is 0 which
specifies that every packet will contain hop sync information. A value greater
than zero specifies the interval at which a packet will contain hop sync
information. The allowable range is 0 to 255 in units of 100 ms. All radios in
the network should have the same Sync Timer Setting.