MSC-HD41L Product Manual
applicable button signal line. If active high signaling is desired, please specify this during purchase, in which
case signal lines are brought high (+3.3V or +5V) to indicate a button press. However, active low is the
recommended option.
Pin # Name Function
6
BTN1 Source 1
7
BTN2 Source 2
8
BTN3 Source 3
9
BTN4 Source 4
5
GND
Ground
DE-9 Pin Numbers
NOTE:
Button interface signal levels depend on whether the device was factory configured for
active low
or
active high
signaling. If unsure what the configuration is, check the voltage level of the button pins in
reference to the ground pin. If the voltage is +3.3V then it is configured for
active low
, if it measures 0V then it
is
active high
.
Button interface signals
•
Active Low:
Connect button pins to ground to activate them.
•
Active High:
An external power supply is required which generates a +3.3V to 5V level, which is
connected to the button pins to activate them. The external power supply ground is connected to the
ground pin.
WARNING:
Care must be taken with Active High mode not to exceed 5V on the button
signal pins or damage may result.
6.3 Serial Interface Pinout
An RS-232 serial port is provided for system control. This interface uses serial signals with 8 data bits, No
Parity, and 1 Stop Bit (8N1). The standard DE-9 pin configuration is used for a DCE device for the RX, TX and
Ground lines. A straight through cable should be used when connecting between a computer’s RS-232 serial
interface and the device. This interface can be used up to 115.2 Kbits/sec.
Pin #
Name
Function
1,4,6,7 NC
Not Connected
2
TX
RS-232 Transmit
3
RX
RS-232 Receive
5
GND
Ground
DE-9 Pin Numbers
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