Microhard Systems MHX-2400, Operating Manual

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MHX-2400 Operating Manual: Chapter 2 Initial Setup and Configuration
IMPORTANT:
For best performance, it is
strongly recommended to use
a separate, linearly regulated
supply for Vcc Radio. Do
not directly feed a switching
power supply into Vcc
Radio.
For OEM design simplicity,
connect both the radio and
logic Vcc connections
together.
Caution:
Using any other power
supply which does not provide the
proper voltage or current could
damage the MHX-2400 module.
1
20
Top View
Antenna Connector
21
40
Vcc Radio
Vcc Radio
Vcc Logic
N/C
/CONFIG
/RESET
GND
GND
GND
N/C
Tx Mode LED
RSSI LED 3
RSSI LED 2
RSSI LED 1
CTS
RTS
DSR
N/C
DTR
TxD
RxD
DCD
Vcc Logic
Vcc Logic
Vcc Logic
Vcc Logic
GND
GND
GND
GND
N/C
N/C
N/C
N/C
N/C
N/C
N/C
N/C
N/C
Rx Mode LED
Figure 1 - Pinout Diagram
The interface connectors and indicator lights are summarized below:
Vcc Radio
- These pins supply power for the MHX-2400’s radio circuitry. Best
performance is achieved by providing linearly regulated voltage to these
pins. It is essential to keep this supply rail as clean as possible -
preferrably by not directly feeding a switching power supply into Vcc
Radio. In addition, it is recommended that Vcc Radio be regulated as
close to 5.5V as possible (without exceeding 5.5V). Running from a 5V
regulator will decrease the transmitted power by roughly 1dB. The linear
regulator must be rated for at least 800 mA
Vcc Logic
- These pins supply power for the MHX-2400’s digital circuitry. It is
recommended you use a linear regulator to feed Vcc Logic. Current
consumption in the logic circuitry is typically 100 mA. The regulator
should be rated for at least 200 mA. To simplify the OEM design, the
Radio Vcc can be connected to the Logic Vcc.
GND
- Ground return pins for both Radio and Logic circuitry
/RESET -
This momentary active low input signal (100 ms typical) resets the
MHX-2400.
/CONFIG -
Leave this pin unconnected. Do NOT ground.
Receive Signal Strength Indicator (RSSI)
- These active high TTL outputs are
designed to drive LED’s. As the signal strength increases, the number of
active RSSI lines increases, starting with RSSI1. When configured as a
Repeater, the module does not indicate RSSI. The LED’s perform a
“scanning” function, blinking on and off in sequence when a Slave or
Repeater modem is searching for synchronization. The current sourcing
capability of these lines is 20 mA.