Multi-Tech Systems MT5600BA-V92 manual Appendix E Pin Descriptions, RS-232 Pin Descriptions

Appendix E – Pin Descriptions

Appendix E - Pin Descriptions

RS-232 Pin Descriptions

Label	Pin	I/O Type	Signal Name/Description
CGND	1	GND	CGND is tied common to GND on the modem’s PCB.
TD	2		Transmitted Data The DTE uses the TD line to send data to the
			modem for transmission over the telephone line or to transmit
			commands to the modem.
RD	3		Received Data The modem uses the RD line to send data received
			from the telephone line to the DTE and to send modem responses to
			the DTE.
RTS	4		Request to Send The RTS signal is used for hardware flow control.
CTS	5		Clear To Send CTS is controlled by the modem to indicate whether or
			not the modem is ready to transmit data. CTS high indicates to the DTE that
			signals presented on TD will be transmitted to the telephone line.
			CTS low indicates to the DTE that it should not transfer data across
			the interface on TD.
DSR	6	Out	Data Set Ready DSR indicates modem status to the DTE. DSR low
			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.
GND	7	GND	Ground.
CFLO	8	CD	Carrier Detect The modem uses the CD line to signal to the DTE
			that a carrier has been detected.
+12V	9		A positive voltage output from the modem used for tests or for
			strapping signals high if needed.
	10		NC
	11		NC
	12		NC
	13		NC
	14		NC
TCLK	15	TC	Transmit Clock Output from modem, used in synchronous mode.
	16		NC
RCLK	17	RC	Receive Clock Output from modem, used in synchronous mode.
V54-2	18	AL	Analog Loop Input to modem to enable analog loop test.
	19		NC
DTR	20	DTR	Data Terminal Ready Input to modem from DTE to control
			answering and disconnection of modem.
RDL	21	RDL	Remote Digital Loop Input to modem to enable RDL test.
RI	22		Ring Indicator RI output high indicates the presence of a ring signal
			on the telephone line.
	23		NC
XCLK	24	XCLK	External Clock Input to modem used in special synchronous
			applications.
TM	25	TM	Test Mode Output from modem to indicate modem is in one of the
			test modes.
Multi-Tech Systems, Inc. MT5600BA-V92 User Guide				53