XECOM
(3)
XE1401
PIN NAME
DESCRIPTION
XE1401 Pin Descriptions
1
RESET
Hardware reset pin, Input, active High, TTL. A high on Pin 1 initiates a hardware reset. An
external reset is not required or recommended. The Reset pulse must be a minimum of 100
milliseconds long.
2
N/C
No Internal Connection
3
RXD
Received Data, Output, TTL. Serial data output to the host. A logic "High" on RXD rep-
resents a "mark" and a logic "Low" represents a "space".
9
\DTR
Data Terminal Ready, Input, active Low, TTL. The "AT&D" command sets the function of
\DTR. The default, AT&D2, requires the host to assert \DTR to permit a modem link. The
modem drops the call in progress if \DTR is revoked and will not connect until \DTR is re-
asserted.
10
\LCS
Loop Current Sense, active Low Input, TTL. A low on \LCS tells the modem that loop
current is flowing through Tip and Ring. This feature is used only in the XE1401B version.
11
\CTS
Clear to Send, Output, active Low, TTL/CMOS. \CTS is used as a Flow Control output
from the modem. The modem revokes \CTS with hardware flow control active to signal the
host that the modem's input buffer is full. The modem reasserts \CTS when the buffer can
accept more data without a buffer overflow.
12
OH
Off-Hook, Output, active High. OH indicates the modem's hookswitch relay is closed.
Hookswitch closure connects the modem to the telephone line.
13
TXD
Transmit Data, Input, TTL. Serial data input from the host. A logic "High" represents a
"mark" and a Low represents a"space", TTL.
14
\RTS
Request to Send, input, active LOW, TTL. The XE1401 uses \RTS for hardware flow con-
trol. When \RTS is revoked and hardware flow control is enabled, the modem will not place
data on RXD.
15
NC
No Internal Connection
16
\RI
Ring Indicator, Output, active Low, TTL. When low indicates the modem is receiving a ring
signal.
18
TIP
Tip connection to the phone line (RJ11 pin3) from the internal DAA. The XE1401 is not
sensitive to the battery voltage polarity across Tip and Ring.
20
RING
Ring connection to the phone line (RJ11 pin4) from the internal DAA.
21
GND
Ground (0 volts)
22
AMP
Audio Output function is set by L & M commands and the value in register S22. This output
can drive a minimum load of 300 ohms.
English ▼
English
Chinese
German
Japanese
Russian
Korean
Spanish
French
Italian
Portuguese
Polish
Vietnamese
Indian
Mexican
British
New Zealand
