AC4490-200M-485 Laird Technologies, AC4490-200M-485 Datasheet - Page 40

• Manufacturer Part Number: AC4490-200M-485
• Description: TXRX 900MHZ 3.3-5.5V TTL 200MW
• Manufacturer: Laird Technologies
• Series: AeroCommr

Specifications of AC4490-200M-485

• Frequency: 902MHz ~ 928MHz
• Data Rate - Maximum: 115.2kbps
• Modulation Or Protocol: FHSS, FSK
• Applications: AMR, Fire & Security Alarms, Telemetry
• Power - Output: 5mW ~ 200mW
• Sensitivity: -110dBm
• Voltage - Supply: 3.3V, 5V
• Current - Transmitting: 68mA
• Data Interface: Connector, 2 x 10 Header
• Antenna Connector: MMCX
• Operating Temperature: -40°C ~ 85°C
• Package / Case: Module
• Wireless Frequency: 900 MHz
• Interface Type: 20-pin mini connector
• Modulation: FHSS, FSK
• Security: 1 byte System ID, DES
• Operating Voltage: 3.3 V to 5.5 V
• Output Power: 200 mW
• Antenna: Integral and External Dipole
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Memory Size: -
• Current - Receiving: -
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant

3 4
C O N F I G U R I N G T H E A C 4 4 9 0
R ea d A D C
The OEM Host issues this command to read any of the three onboard
10-bit A/D converters.
Command Mode, the transceiver will not process the command until
there is no activity on the network.
therefore useful for detecting interfering sources but will not report the
RSSI from a remote transceiver on the network. The equations for
converting these 10 bits into analog values are as follows:
Analog Voltage = (10 bits / 0x3FF) * 3.3V
Temperature (
RSSI value (dBm) = -105 + (0.22 * (0x3FF - 10 bits))
R ep o r t L a st V a li d RS S I
Since RSSI values are only valid when the local transceiver is receiving
an RF packet from a remote transceiver, instantaneous RSSI can be
tricky to use. Therefore, the transceiver stores the most recent valid
RSSI value as measured the last time the transceiver received a packet
or beacon. The Host issues this command to retrieve that vale.
Note: This value will default to 0xFF on a Client and 0x00 on a Server if
no valid RSSI measurement has been made since power-up.
o
Signal Strength (dBm)
C) = ((Analog Voltage - 0.3) / 0.01) - 30
-36 to -22
-42 to -39
-12 to -6
Because the RF is still active in On-the-Fly
-2 to 1
-46
-49
-52
-56
-59
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T a b l e 1 5 : R e c e i v e d S i g n a l S t r e n g t h
The Read RSSI command is
RSSI Value (Hex)
0x0E
0x0D
0x0C
0x0B
0x0C
0x0D
0x0E
0x1C
0x11
0x17
Signal Strength
Command: <0xCC> <0x21> <Port>
Number of Bytes Returned: 3
Response: <0xCC> <Hi ADC> <Lo ADC>
Parameter Range:
<Port>
<Hi ADC>
<Lo ADC>
Command: <0xCC> <0x22>
Number of Bytes Returned: 2
Response: <0xCC> <Last Valid RSSI>
(dBm)
-62
-66
-69
-72
-76
-79
-82
-86
-89
-92
= 0x00: AD In
= MSB of requested 10-bit ADC value
= LSB of requested 10-bit ADC value
0x01: Temperature
0x02: RSSI
RSSI Value (Hex)
0xAD
0xBD
0x2B
0x9A
0x40
0x55
0x62
0x71
0x78
0x84