Microhard Systems MHX-900, Operating Manual

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4 MHX-900 Operating Manual: Chapter 2 Initial Setup and Configuration
For maximum power, use
separate power supplies for
the radio and the digital
electronics.
For OEM design simplicity,
connect both the radio and
logic VCC connections
together. This saves a
regulated power supply.
Caution: Using any other power
supply which does not provide the
proper voltage or current could
damage the MHX-900 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
The interface connectors and indicator lights are summarized below:
Vcc Radio - These connections supply power for the MHX-900 module’s radio
deck electronics. For 1 watt maximum output, the required supply rating
should be 5.25 VDC +- 5%. Limiting this to 5.0 Vdc will limit the output
power slightly. Required current depends on transmit duration and output
power. Maximum current at full transmit power is 600 mA DC.
Vcc Logic - These connections supply power for the MHX-900 module’s digital
electronics. To simplify the OEM design, the Radio VCC can be
connected to the Logic VCC. Maximum current while transmitting is
approx. 100 mA DC.
GND - These are the Ground supply connections for the digital and radio
electronics.
/RESET - This momentary active low input signal (100 ms typical) resets the
digital electronics.
/CONFIG - Leave this pin unconnected. Do NOT ground.
Receive Signal Strength Indicator (RSSI) LEDs - These outputs show the
quality/strength of the received signal. As the signal strength increases,
the number of active outputs increase incrementally.
Data Port (DCE) - Pins 21 through 28 inclusive. This port is used to interface
the MHX-900 module to a DTE device and operates at 2400 to 115,200
bps. The same port is used to configure the modem by interfacing to the
host microprocessor. See Appendix B for details on the serial interface
signals.
RX Mode LED - This active low output indicates when the modem receives data
over the wireless link, as well as during internal carrier search and
synchronization operations.
TX Mode LED - This active low output indicates that the modem is transmitting
data wirelessly. This light flashes during initial startup and carrier
synchronization.
Antenna Connector - The antenna is attached to this connection.
N/C - These pins are reserved for future use. Do not connect to this pins.