FreeWave Technologies Inc. 1521131FFF 사용자 설명서

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 Spread Spectrum Wireless Data Transceiver User Manual 
LUM0002AG Rev A 
Version 7.0 
34 
42 
63 
85 
106 
127 
149 
170 
191 
213 
234 
47 
69 
90 
111 
133 
154 
175 
197 
218 
239 
53 
74 
95 
117 
138 
159 
181 
202 
223 
245 
58 
79 
101 
122 
143 
165 
186 
207 
229 
250 
63 
85 
106 
127 
149 
170 
191 
213 
234 
255 
The following table defines the Maximum packet size in bytes by way of charting the Min Packet Size 
setting versus the Max Packet Size setting where the RF Data Rate is set to 3.  Using the default settings, 
the actual maximum packet size, in bytes, is 172.  
Maximum Packet Size Definition with RF Date Rate of 3 
 
Max Setting 
Min Setting 
24 
40 
56 
72 
88 
104 
120 
136 
152 
12 
28 
44 
60 
76 
92 
108 
124 
140 
156 
16 
32 
48 
64 
80 
96 
112 
128 
144 
160 
20 
36 
52 
68 
84 
100 
116 
132 
148 
164 
24 
40 
56 
72 
88 
104 
120 
136 
152 
168 
28 
44 
60 
76 
92 
108 
124 
140 
156 
172 
32 
48 
64 
80 
96 
112 
128 
144 
160 
176 
36 
52 
68 
84 
100 
116 
132 
148 
164 
180 
40 
56 
72 
88 
104 
120 
136 
152 
168 
184 
44 
60 
76 
92 
108 
124 
140 
156 
172 
188 
 
Referencing the default settings, the Master will transmit up to 172 bytes on every hop. If fewer than 172 
bytes are transmitted, the balance is allocated to the Slave's transmission, plus the quantity in the Min 
Packet Size Setting.  
For example, if a Master transmits 100 bytes, the Slave will then have a total of 116 bytes available 
(72(“leftover bytes”) + 44 (Min packet size)).  
(3)
 
X
MIT 
R
ATE
 
Two settings for the Transmit Rate parameter are available. The setting for normal operation of the 
transceiver is a Transmit Rate 1. Transmit Rate 0 is useful to qualitatively gauge signal strength in Point 
to Point mode. When set to Transmit Rate 0, the transceivers will transmit back and forth continuously 
regardless if they have any actual data. In Point-to-Point operation, Transmit Rate 0 should be used only 
as a diagnostic tool and not for normal operation.  The strength of the signal may be gauged by the Clear 
to Send LED. A solid red CTS LED indicates a strong signal; a blinking CTS LED indicates a weaker 
signal. 
(4)
 
RF
 
D
ATA 
R
ATE 
 
FreeWave transceivers have two settings for the RF Data Rate (2, 3). RF Data Rate should not be 
confused with the serial port Baud Rate. Setting 2 (RF Speed of 153.6kbps) should be used when the 
transceivers are close together and data throughput needs to be optimized. Setting 3 (RF Speed of 
115.2kbps) should be used when the transceivers are farther away and a solid data link is preferred over 
data throughput. 
Note:   In MultiPoint networks, the RF Data Rate must be set identically in all transceivers. Any 
transceiver with an RF Data Rate different from the Master will not establish a link.   
 
In Point to Point networks the Master’s settings take precedence over the Slave.