Multitech MT-SMI-DK Development Manual page 14

Pin Signal Name
34 –RXD
35 –TXD
36 –RI
37 –DSR
38 –CTS
39 –DCD
40 –DTR
41 GND
42 SPK-
43 SPK+
44 PCM_DO
45 PCM_DI
46 PCM_FS
47 PCM_CLK
48 GPIO 1
49 GPIO
1
50 GPIO 1
51 GPIO 1
52 DBTX/GPIO
53 DBRX/GPIO
54 GPIO
55 Heartbeat
Universal Socket Developer Guide
In/Out Description
O Received Data. The SocketModem uses the RXD line to send data to the DTE and
to send SocketModem responses to the DTE. In command mode, –RXD data
presents the SocketModem responses to the DTE. SocketModem responses take
priority over incoming data when the two signals are in competition for –RXD.
When no data is transmitted, the signal is held in mark condition.
I Transmitted Data. The DTE uses the –TXD line to send data to the SocketModem
for transmission or to transmit commands to the SocketModem. The DTE holds
this circuit in mark state when no data is being transmitted or during intervals
between characters.
O RING (Active Low). Incoming ring signal from phone.
Ring Indicate. –RI output ON (low) indicates the presence of an ON segment of a
ring signal on the telephone line. The modem will not go off-hook when –RI is
active; the modem waits for –RI to go inactive before going off-hook.
SocketWireless Bluetooth (MTS2BTSMI): Strobes 1/sec for slave indication.
O Data Set Ready (Active Low). –DSR indicates SocketModem status to the DTE. –
DSR OFF (high) indicates that the DTE is to disregard all signals appearing on the
interchange circuits except Ring Indicator (–RI). It reflects the status of the local
data set and does not indicate an actual link with any remote data equipment.
O Clear to Send (Active Low). –CTS is controlled by the SocketModem to indicate
whether or not the SocketModem is ready to transmit data. –CTS ON indicates to
the DTE that signals on TXD will be transmitted. –CTS OFF indicates to the DTE that
it should not transfer data on TXD.
O Data Carrier Detect (Active Low). –DCD output is ON (low) when a data
connection is established and the SocketModem is ready to send/receive data.
I Data Terminal Ready (Active Low). The –DTR input is turned ON (low) when the
DTE is ready to communicate. –DTR ON prepares the modem to be connected,
and, once connected, maintains the connection. –DTR OFF places the modem in
the disconnect state under control of the &Dn and &Qn commands.
When the –DTR pin is not in use, it should be tied low.
Note:
GND Logic Ground.
O Cellular GPRS, CDMA, and EDGE. Negative analog speaker output.
O Cellular GPRS, CDMA, and EDGE. Positive analog speaker output.
O Digital voice custom factory option.
I Digital voice custom factory option.
O Digital voice custom factory option.
O Digital voice custom factory option.
I/O General Purpose Input/Output. User-configurable input or output pin.
I/O General Purpose Input/Output. User-configurable input or output pin.
I/O General Purpose Input/Output. User-configurable input or output pin.
I/O General Purpose Input/Output. User-configurable input or output pin.
O Not currently used.
I Not currently used.
N/A Reserved for future use.
N/A Reserved for future use.
CHAPTER 2 – UNIVERSAL SOCKET PINOUT
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