RF400 Series Spread Spectrum Data Radio/Modems

Retries”, “Time-slots for Random Retry”, and “Bytes Transmitted before

Delay” settings.

STANDARD RETRY LEVELS

 

Retry

Maximum

Time-Slots for

Bytes Transmitted

Menu

Level

Retries

Random Retry

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.

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