Cermetek XE2422H User manual
Low-Cost, Low-Speed Surface-Mount Modem
©2009 Cermetek Microelectronics, Inc. Page 1 Document No. 607-0044 Revision A (12/11)
DESCRIPTION
The Cermetek XE2422H is a complete 2400 bps
modem in a miniature surface-mount module. It
permits the designer to easily incorporate dial-up
communications into set top box, security,
vending, or point-of-sale applications.
The XE2422H is a complete modem not just a
modem chip. Connections to the micro-controller
serial port and to the telephone line are all that is
required to design-in the XE2422H. As a
complete modem, Cermetek includes transferable
FCC Part 68 Registration. Eliminating the need
for Cermetek customers to under go FCC Part 68
testing.
The XE2422H provides the lowest total cost of
ownership. As a complete modem, it eliminates
modem design and certification costs. It reduces
assembly costs by replacing multiple components
with a single, surface-mount module. And all of
this is provide at a low per unit cost of less than
twenty dollars in volume.
FEATURES
Small Size: 1.60” by 0.80” by 0.152”
Data transfer rates from 300 bps to 2400 bps
• Supports V.21, V.22, V.22bis, V.23, Bell 103,
Bell 212A modem protocols
• Supports Pulse and FSK Alarm formats
Serial data rates to 115,200 bps.
Control and configuration via AT Commands
3.3 and 5 volt compatible Serial Interface
Shared Line Features prevent interference with
voice communications on an extension
telephone.
Complete integrated DAA.
User Transferrable FCC Part 68 Registration
UL60950 Recognition
Low Operating Power, 3.3 Volts, 50 mW;
Sleep Mode with Wake-on-Ring feature
Power Down reduces current draw to 100 A
XE2422H BLOCK DIAGRAM
Cermetek Microelectronics, Inc XE2422H Surface Mount Modem Module
©2009 Cermetek Microelectronics, Inc. Page 2 Document No. 607-0028 Revision C (10/09)
XE2422H Mechanical Specifications
E
F
FF I
A
J
HG C
D
B
INCHES MILLIMETERS
DIMENSIONS MIN TYP MAX MIN TYP MAX
A 1.595 1.600 1.605 40.51 10.64 40.77
B 0.795 0.800 0.805 20.19 20.32 20.45
C 0.147 0.152 0.157 3.73 3.86 3.99
D 0.095 0.100 0.105 2.41 2.54 2.67
E 0.055 0.060 0.065 1.40 1.52 1.65
F 0.095 0.100 0.105 2.41 2.54 2.67
G 1.045 1.050 1.055 26.54 26.67 26.80
H 0.495 0.500 0.505 12.57 12.70 12.83
I 0.995 1.000 1.005 25.27 25.40 25.53
J 0.395 0.400 0.405 10.03 10.16 10.29
Cermetek Microelectronics, Inc XE2422H Surface Mount Modem Module
©2009 Cermetek Microelectronics, Inc. Page 3 Document No. 607-0028 Revision C (10/09)
XE2422H Pin Configuration
Top View
1
2
3
4
5
6
7
13
12
11
10
9
8
Tip
Ring
/DCD
/DTR
/RI
Reserved
GND
VCC
/INT
/CTS
/RESET
RXD
TXD
Pin Descriptions
PIN NAME DESCRIPTION
1 TIP The Ring and Tip signals connect the modem to the telephone line. FCC Part 68
Rules require a 1500 volt isolation barrier between the telephone line and all other
circuits. This isolation must be preserved throughout the system.
The telephone company places a DC “Battery” voltage across Tip and Ring on public
switched telephone lines. The XE2422H operates regardless of the polarity of this
voltage. The “Battery” voltage drives up to 120 milliampere of DC loop current.
UL60950 requires minimum creepage and clearances distances between the Tip and
Ring traces and all other circuits. Clearance is the shortest distance between
conductive circuits; creepage is the distance between conductive points along the
surface
2 RING The Ring and Tip signals connect the modem to the telephone line. FCC Part 68
Rules require a 1500 volt isolation barrier between the telephone line and all other
circuits. This isolation must be preserved throughout the system.
The telephone company places a DC “Battery” voltage across Tip and Ring on public
switched telephone lines. The XE2422H operates regardless of the polarity of this
voltage. The “Battery” voltage drives up to 120 milliampere of DC loop current.
UL60950 requires minimum creepage and clearances distances between the Tip and
Ring traces and all other circuits. Clearance is the shortest distance between
conductive circuits; creepage is the distance between conductive points along the
surface.
3 /DCD /DCD is an active low output from the modem that indicates the presence of a valid
carrier signal. The SE2 register controls /DCD in the XE2422H. The default state is for
/DCD to be disabled ATSE2=04 enables /DCD.
Cermetek Microelectronics, Inc XE2422H Surface Mount Modem Module
©2009 Cermetek Microelectronics, Inc. Page 4 Document No. 607-0028 Revision C (10/09)
PIN NAME DESCRIPTION
4 /DTR /DTR is an active low input to the modem. The operation of /DTR is controlled by
register SE2 and is normally disabled. When enabled, the modem will exit data mode
and enter command mode if /DTR is removed while the modem is on-line. In Pulse
and FSK Alarm modes raising /DTR is the only was to disconnect the data link.
5 /RI The /RI signal reports on the presence of an incoming ring signal. When a ring
occurs across Tip and Ring, the /RI output goes low and toggles with the cadence of
the ring signal. /RI is controlled by register S0D bit 6. The default condition is for /RI to
be disabled.
6 RESERVED Reserved for future use
7 GROUND Ground provides the reference voltage for all host interface signals.
8 TXD TXD provides the path for transmitted data and modem commands to be passed from
the host controller to the modem. A logic high on TXD represents a “Mark” condition
and a logic low represents a “Space” condition.
9 RXD RXD provides the path for received data and modem responses to be sent from the
modem to the host controller. A logic high on RXD represents a “Mark” condition and
a logic low represents a “Space” condition.
10 /RESET /RESET is an active low input which initiates a modem hardware reset.
11 /CTS /CTS is an active low output from the modem. The modem asserts /CTS to indicate
that it can accept data from the terminal equipment on TXD.
12 /INT /INT provides an active low hardware interrupt signal from the XE2422H. The
operation of this interrupt pin is programmable using registers SE2 and S08. /INT can
be programmed to indicate Loss of Carrier, Wake-on-Ring, Loss of Loop Current, or
Shared Line Activity. Once triggered the /INT line remains active until cleared by the
AT:I command.
13 VCC VCC provides 3.3 volt power to the modem.
Cermetek Microelectronics, Inc XE2422H Surface Mount Modem Module
©2009 Cermetek Microelectronics, Inc. Page 5 Document No. 607-0028 Revision C (10/09)
XE2422H Electrical Specifications
PARAMETER MIN TYP MAX UNITS COMMENTS
VCC 3.0 3.3 3.6 VOLTS
15 mA On-Line
10 mA Sleep
ICC
1 mA Power Down
RING VOLTAGE DETECT 26 150 VRMS Type B Ringer
RING FREQUENCE DETECTED 15.3 68 Hz Type B Ringer
TELEPHONE LOOP CURRENT 16 40 120 mA
LINE IMPEDENCE 600 Ohms
DATA TRANSMIT LEVEL -9.0 dBm
DTMF TRANMIST LEVEL -2.5 0 dBm Average over a 3 second interval
Voh 2.4 Volts
Vol 0.4 Volts
Vih 2.0 5.0 Volts
ViL -0.3 0.8 VCC
Cermetek Microelectronics, Inc XE2422H Surface Mount Modem Module
©2009 Cermetek Microelectronics, Inc. Page 6 Document No. 607-0028 Revision C (10/09)
XE2422H Surface-Mount Soldering Instructions
The XE2422H is subject to damage if overexposed to heat during solder reflow operations. Following the
soldering instructions below will ensure that the process of soldering the module to the board does not
damage the modem.
Maximum Temperature 235OC
Maximum Time at 235OC 15 Seconds
Maximum Time above Eutectic (150OC) 90 Seconds
Maximum Preheat Dwell Time 180 Seconds
Maximum Recommended Solder Temperature Profile
Cermetek Microelectronics, Inc XE2422H Surface Mount Modem Module
©2009 Cermetek Microelectronics, Inc. Page 7 Document No. 607-0028 Revision C (10/09)
XE2422H Recommended Landing Pattern
Pad Dimensions: Oval 0.130 inches by 0.070 inches
Pad Extensions beyond XE2422H PCB: 0.040 inches
Row Center to Center: 0.74 inches
Warning: No Vias, Traces or other Copper should be placed under the XE2422H module
Cermetek Microelectronics, Inc XE2422H Surface Mount Modem Module
©2009 Cermetek Microelectronics, Inc. Page 8 Document No. 607-0028 Revision C (10/09)
XE2422H Typical Connection Diagram
VCC
/DCD
/CTS
RXD
TXD
/RI
/Reset
/INT
GND
RING
TIP (22)
RJ11
C1 C2
VCC
F1
To SystemReset
To Host SerialPort
To System Interrupt
XE2422H
Parts List for XE2422H Typical Connection Diagram
Reference
Designation
Qty
Description
C1, C2 2 Cap, 1000 pFd, 1500 V minimum
F1 1 PTC, TR600-150
Notes:
1 Capacitors, C1 and C2, may be required for EMI filtering in your system. Without these components
you may experience unintended radiation when the telephone cable is attached. C1 and C2 are high-
voltage capacitors. We recommend the Johanson Dielectrics 502S47N102KV6T. This 1000 pfd, 3000
volt capacitor will direct the high frequency harmonics to the system ground. These capacitors must be
rated at a minimum of 1500 volts to maintain the isolation required by FCC Part 68 Rules.
3. F1 is a positive thermal coefficient (PTC) device which protects the modem from excessive current flow.
These devices are required for your system to pass UL60950. Fuses may be used in place of the
PTC’s
Cermetek Microelectronics, Inc XE2422H Surface Mount Modem Module
©2009 Cermetek Microelectronics, Inc. Page 9 Document No. 607-0028 Revision C (10/09)
XE2422H DESIGN NOTES
The following design notes are intended to assist the developer in achieving maximum utility from the XE2422H
modem module.
XE2422H Shared Line Features
The XE2422H includes the ability to monitor telephone line conditions before, after and during calls. This
allows the XE2422H to avoid conflicts with other equipment connected to the telephone line. There are two
modes of operation for the XE2422H Shared Line Features; Connect Detect and Handset Interrupt.
Connect Detect
The XE2422H register SDB monitors the voltage level on the telephone line when the modem is on-hook.
The XE2422H checks the value of register SDB before attempting to go off-hook to avoid interrupting a call
in progress. The nominal value for loop voltage on the telephone line is typically 48 volts. A reduced
voltage level indicates that the line is either disconnected from the modem or is currently in use.
Register SDB is an 8 bit register. It stores the loop voltage as a 2’s complement number with each bit
representing 1 volt. The Most Significant Bit represents the polarity of the loop voltage.
Handset Interrupt:
Handset Interrupt permits the modem to yield the telephone line when other equipment connected to the
telephone line goes off-hook. This prevents the modem from blocking outgoing emergency calls when the
line is shared as in a residential application. Handset Interrupt is accomplished by monitoring the loop
current through the modem while the modem is off-hook. The loop current will drop when another piece of
equipment goes off-hook on the same telephone line.
The XE2422H constantly monitors and stores the loop current value in Register SF3 in 1.1 milliamp
increments. The value of SF3 is regularly updated. The value of SF3 is compared to the Handset Interrupt
threshold in register S12. If the value of SF3 is lower than the value of S12 by at least the amount of the
Handset Interrupt Differential Current Threshold, S11, then the XE2422H assumes the equipment on an
extension telephone has gone off-hook. The modem then issues the Handset Interrupt response “i” and if
so configured issues an Interrupt to the systems host controller. The host controller determines if the call
should be terminated to yield the telephone line to the extension.
XE2422H AT Commands
The XE2422H uses a simplified "AT" command set for configuration and control. This section describes
the AT command format and lists the AT commands, registers and result codes. XE2422H "AT" commands
have three operational modes; command mode, alarm mode and data mode. The Data Rate for the
XE2422H is set by Register SE0.
Data Mode: The XE2422H enters data mode after it connects to a remote modem and issues the
appropriate result code. In the data mode the modem sends all data presented on Transmit Data (TXD) to
the remote modem and puts data from the remote modem onto Received Data (RXD). When the modem
exits data mode, it issues a "NO CARRIER" result code.
Command Mode: The XE2422H enters command mode on power-up, reset, a lost connection, or receipt
of the escape code. In command mode the modem accepts commands from the host on transmit data.
Appropriate result codes are returned on RXD.
Cermetek Microelectronics, Inc XE2422H Surface Mount Modem Module
©2009 Cermetek Microelectronics, Inc. Page 10 Document No. 607-0028 Revision C (10/09)
Command Line Format
Command lines issued to the modem follow a strict format. Each command line begins with the prefix AT.
All commands except the “z” command must be entered in upper case characters. The command line is a
string of commands between the AT prefix and the carriage return which terminates the command. The
command buffer stores the command line and executes it upon receipt of a carriage return. Commands
will be executed in the sequence they appear in the command line.
Result Codes - The modem issues a result code after each command line. Result codes may be sent as
single characters or single characters followed by a carriage return.
Alarm Mode:
The XE2422H supports a unique set of commands to establish alarm industry connections. Both Pulse
messaging and FSK formats are supported. The AT!1 command initiates Pulse messaging and AT!2
initiates FSK messaging. The ATD command must precede either AT! command to begin the Alarm
transaction. In Alarm mode, /DTR must be removed to disconnect the modem link. /DTR is activated by
setting register SE2 bits 4 and 5.
Pulse Mode: In Pulse Mode messages are passed using DTMF tones. The receiving station
acknowledges receipt of the message by transmitting the “Kissoff” tone. A sample transaction is shown
below.
Alarm Panel XE2422H
ATDT#!1<message 1><CR>
K
!<message 2><CR>
K
!<message n><CR>
K
Disconnect is accomplished by raising /DTR.
FSK Mode: In FSK Mode messages are passed on a 300 bps, half-duplex carrier signal. The X1, X2, and
X3 commands switch the modem between monitoring the line for acknowledgments (X1), transmitting
messages (X2), and receiving messages (X3). As in the pulse mode disconnect is only possible by pulling
the /DTR signal high.
Cermetek Microelectronics, Inc XE2422H Surface Mount Modem Module
©2009 Cermetek Microelectronics, Inc. Page 11 Document No. 607-0028 Revision C (10/09)
XE2422H AT Commands
An asterisk indicates the factory default
A - Answer Command -
D - Dial Command -
0-9, A-D, #, * = Dialing Digits
P = Pulse dial
T = Tone dial
, = Pause for two seconds
I = Pause for 125 milliseconds
; = Return to the command state
En - Command Echo
n=0 Do not echo commands
n=1 Enable command echo *
Hn - Switch Hook Control -
n=0 Switch hook relay opens
n=1 Switch hook relay closes
In - Modem Identification
:I Read Interrupt Register - Read and reset
the interrupt status register S09
O - Return On Line
SR? - Read Value of register R
SR=n - Write value “n” into register “R”.
The values of both “n” and “R” are
hexadecimal.
Vn - Result Codes -
n=0 Single Character Result Codes
n=1 Result Codes followed by a Carriage
Return*
Z - Reset -
z - Wake from Sleep Mode on Ring
!1<message> - Switch to Pulse Mode: This
command must follow the dialing command in
the same command string.
!2<message> - Switch to FSK Mode: This
command must follow the dialing command in
the same command string. This command allows
the modem to establish a 300 bps half-duplex
FSK signal.
X1 - FSK Signal Search: Turns off the modem
transmitter and monitors the line for an
acknowledgment.
X2 - Return On-line as Transmitter: Places the
modem in the transmit mode during FSK half-
duplex operation.
X3: - Return on-line as Receiver: Places the
modem in the receive mode during FSK half-
duplex operation.
~ - Resend Last Pulse Mode Message:
Cermetek Microelectronics, Inc XE2422H Surface Mount Modem Module
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XE2422H RESPONSES
Result Code Description
a British Caller ID Tone Detected
b Busy Tone Detected
c Connect
d Connect 1200
f Battery Voltage Reversal Detected
H Modem automatically hung up in Security Mode
I Parallel Handset Returned On-Hook
i Handset Interrupt Detected
K Kissoff Tone Detected in Security Mode
k Kissoff Tone exceeds Limit set by S36
L Phone Line Detected
l No Phone Line Detected
m Caller ID Signal Detected
N No Carrier Detected
n No Dial Tone
O OK Response
R Ringing
r Ringback Tone Detected
t Dial Tone Detected
x Over-current Condition Detected
v Connect in V.23 originate mode
^ Kissoff Tone Detection Required
, Dialing Complete
Cermetek Microelectronics, Inc XE2422H Surface Mount Modem Module
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XE2422H REGISTER SETTINGS
XE2422H register values are stored in Hex format. An asterisk “*” signifies the default setting of a bit-
mapped register.
S00 Answer on nth Ring: S00 sets the modem to automatically answer on the nth ring. Setting S00 to
0 disables automatic answer.
.. Range: ..00 to 7F (0 to 127 rings)
.. Units......Rings
.. Default...00 (Auto Answer Disabled)
S01 Wait to Dial: S01 determines the maximum time the modem will wait to dial
.. Range: ..0 to 6D (0 to 109 seconds)
.. Units .....Seconds
.. Default...02 (2 seconds)
S02 Wait for Dial Tone S02 determines how long the modem waits for Dial Tone before hanging up.
Range: ..00 to 6D (0 to 109 seconds)
.. Units......Seconds
.. Default...03 (3 seconds)
S03 Carrier Off Disconnect Delay: S03 determines how long carrier must be lost before modem
disconnect.
.. Range: ..00 to 7F (0 to 6.78 seconds)
.. Units......0.0533 Seconds
.. Default...0E (0.75 seconds)
S04 DTMF Duration and Spacing: S04 sets duration and spacing of DTMF dialing tones.
.. Range: ..00 to 7F (0 to 211 milliseconds)
.. Units......1.666 milliseconds
.. Default...30 (80 milliseconds)
S05 Duration Off-Hook during Pulse Dialing: S05 defines how long the hookswitch is active between
dialing pulses.
.. Range: ..00 to 7F (0 to 211 milliseconds)
.. Units......1.666 milliseconds
.. Default...18 (40 milliseconds)
..
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S06 Duration of Dialing Pulses: S06 determines how long the modem goes on-hook to generate dialing
pulses....
.. Range: ..00 to 7F (0 to 211 milliseconds)
.. Units......1.666 milliseconds
.. Default...24 (60 milliseconds)
S07 Modem Protocol Selection: S07 sets the protocol and speed of the modem connection.
Protocol Data Rate Register Value
V.22bis 2400 bps 06 *
V.22 1200 bps 02
V.21 300 bps 03
Bell 212A 1200 bps 00
Bell 103 300 bps 01
S08 Interrupt Control Register: S08 is a bit-mapped register which defines the events that will cause
the /INT signal to be activated. Default = 00
.. Bit # Definition Action
.. 7 Issue Interrupt when Carrier Detect is lost 0 = No Interrupt *
.. 1= Activate Interrupt
.. 6 Issue Interrupt on Ring with Wake-on-Ring selected 0 = No Interrupt *
.. 1= Activate Interrupt
.. 5 Issue Interrupt on Handset Interrupt Detection 0 = No Interrupt *
.. 1= Activate Interrupt
.. 4 Issue Interrupt on No Connect Detection 0 = No Interrupt *
.. 1= Activate Interrupt
.. 3 Issue Interrupt on Ring Detection 0 = No Interrupt *
.. 1= Activate Interrupt
.. 2 Issue Interrupt on Caller ID 0 = No Interrupt *
.. 1= Activate Interrupt
.. 1 Issue Interrupt on Over-current Detection 0 = No Interrupt *
.. 1= Activate Interrupt
.. 0 Reserved
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S09 Interrupt Status Register: S09 is a bit-mapped register. The active bit indicates the cause of the
most recent interrupt. S09 is cleared when read on receipt of the :I command. Default = 00
. Bit#.......Definition
.. 7 Interrupt issued when Carrier Detect was lost
.. 6 Interrupt issued when a Ring was detected with Wake-on-Ring selected
.. 5 Interrupt issued on Handset Interrupt Detection
.. 4 Interrupt issued on No Connect Detection
.. 3 Interrupt issued on Ring Detection
.. 2 Interrupt issued on Caller ID
.. 1 Interrupt issued on Over-current Detection
.. 0 Reserved
S0C Modem Function Register: S0C is a bit-mapped register which controls the designated modem
functions. Default = 00
.. Bit # Definition Action
.. 7 Enable Carrier Detect IO pin 0 = No DCD output *
.. 1= DCD Active
.. 6 Reserved
.. 5 Enable Caller ID 0 = No Caller ID *
.. 1= Caller ID Active
.. 4:3 Reserved
.. 2 Blind Dialing, dialing without detecting dial tone 0 = Dial Tone Required *
.. 1 = Blind Dialing Selected
.. 1:0 Reserved
S0D Modem Function Register: S0D is a bit-mapped register which controls the designated modem
functions. Default = 00
.. Bit # Definition Action
.. 7 Reserved
.. 6 Enable Ring Indicate IO pin 0 = No RI output *
.. 1 = RI Active
.. 5:4:3 Reserved
.. 2 Disconnect upon detection of a Busy Signal 0 = Disabled *
.. 1 = Hang-up on Busy Detect
.. 1 Disconnect on Handset Interrupt detection 0= Disabled *
.. 1 = Enabled
.. 0 Reserved
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S0E Pulse Dialing Interdigit Delay: S0E determines the length of the time between numbers dialed
using dialing pulses. The minimum time between digits is 64 milliseconds. The value of S0E adds to
that 64 millisecond delay in 10 millisecond increments
.. Range: ..00 to 7F (64 to 1374 milliseconds)
.. Units......10 milliseconds
.. Default...46 (764 milliseconds)
S0F Escape Character: S0F defines the character to be used in the escape sequence to move from
data mode to command mode. Values of 0 to 127 select valid ASCII characters.
.. Range: ..00 to 7F
.. Units......ASCII Character
.. Default...2B (+)
S10 Escape Code Guard Timer: S10 defines the duration of the guard timer surrounding the escape
sequence. The guard time is the time preceding and following the escape sequence during which
any character received by the modem will abort the escape sequence.
.. Range: ..00 to 7F (0 to 6.78 seconds)
.. Units......0.0533 Seconds
.. Default...13 (1 second)
S11 Handset Interrupt Differential Current Threshold: S11 sets the differential loop current threshold
for the XE2422H handset Interrupt detection algorithm. If loop current falls by the value of S11 below
the value of S12, Handset Interrupt is activated.
.. Range: ..00 to 07 (0 to 7 milliamps)
.. Units......1 Milliamp
.. Default...04 (4 milliamps)
S12 Handset Interrupt Current Threshold: S12 sets the loop current threshold for the XE2422H
Handset Interrupt detection algorithm. If loop current falls by the value of S11 below the value of S12,
Handset Interrupt is activated.
.. Range: ..00 to 64 (0 to 100 milliamps)
.. Units......1 Milliamp
.. Default...00 (0 milliamps)
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S15 Modem Link Control Register: S15 selects modem guard tones, calling tones and data format..
Default = 04
.. Bit # Definition Action
.. 7 Reserved
.. 6 Transmit V.25 Calling Tone 0 = Disabled *
.. 1 = Calling Tone Active
.. 5 Transmit 550 Hz Guard Tone 0 = Disabled *
.. 1= 550 Hz Guard tone Active
.. 4 Transmit 1800 Hz Guard Tone 0 = Disabled *
.. 1= 1800 Hz Guard tone Active
.. 3 Number of Stop Bits 0 = 1 Stop Bit *
.. 1 = 2 Stop Bits
.. 2:1 Number of Data Bits 00 = 6 Data Bits
.. 01 = 7 Data Bits
.. 10 = 8 Data Bits *
.. 11 = 9 Data Bits
.. 0 Reserved
S29 Handset Interrupt Blocking Time: S29 provides a set duration for blocking the Handset Interrupt
feature to avoid false detections. This timer is activated by S82.
.. Range: ..00 to 7F (0 to 63.5 Seconds)
.. Units......0.5 Seconds
.. Default...00 (disabled)
S37 Carrier Detect Recovery Time: S37 determines how long after being lost the data carrier signal
must be detected before the modem recognizes it as being recovered.
.. Range: ..00 to 7F (0 to 211 milliseconds)
.. Units......1.66 milliseconds
.. Default...20 (53.33 milliseconds)
S39 Carrier Detect Response Time: S39 determines how long the modem will wait for the initial data
carrier signal to be detected before aborting a call..
.. Range: ..00 to 7F (0 to 127 Seconds)
.. Units......1 Second
.. Default...3C (60 Seconds)
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S62 Result Code Register: S62 allows selection of specific modem result codes. Default = 41
.. Bit # Definition Action
.. 7 Reserved
.. 6 Over-current Result code “x” 0 = Result Code “x” supported
.. 1 = Disabled *
.. 5:4:3 Reserved
.. 2 Handset Interrupt Result Codes “I” and “i” 0 = Disabled *
.. 1 = Support result codes “I’ and “i”
.. 1 Connect Detect Result Codes “L” and “l” 0 = Disabled *
.. 1 = Support result codes “L’ and “l”
.. 0 Ring Result Code “R” 0 = Disabled
.. 1 = Result Code “R” supported
S82 Loop Current Register: S82 allows selection of specific modem result codes. Default = 08
.. Bit # Definition Action
.. 7:6:5:4 Reserved
.. 3 Detect Loss of Loop Current 0 = Disabled
.. 1 = Enabled *
.. 2:1 Block Handset Interrupt on initial connection 00 = No Handset Interrupt Blocking *
.. 01 = Blocked during dialing
.. 10 = Blocked unit S29 Time out
.. 11 = Blocked unit Carrier Detect
.. 0 Reserved
SDB Line Voltage Status: SDB is a read only register that stores the value of the loop voltage in two’s
compliment form. The most significant bit, Bit 7, indicates the polarity of the voltage on Tip and Ring.
.. Units......1 Volt
.. Default...00 (Tip and Ring Voltage less than 3 volts)
Cermetek Microelectronics, Inc XE2422H Surface Mount Modem Module
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SE2 Interrupt Enable: SE2 activates the XE2422H Interrupt output. Default = 00
.. Bit # Definition Action
.. 7:6: Interrupt Output Control 00 = Disabled *
.. 01 = Disabled
.. 10 = Disabled
.. 11 = Interrupt Output Enabled
.. 5:4 /DTR Control 00 = Disabled *
.. 01 = Disabled
.. 10 = Disabled
.. 11 = /DTR Enabled
.. 3:2 /DCD 00 = /DCD Disabled*
.. 01 = /DCD Enabled
.. 10 = /DCD Disabled
.. 11 = /DCD Disabled
.. 1:0 Reserved
SF1 Power Down Register: SF1 allows the XE2422H to be placed in power down mode. The modem
draws only about 100 microamps in Power down mode. Default = 0C
.. Bit # Definition Action
.. 7 Reserved
.. 6 Power Down Mode 0 = Normal Operation
.. 1 = Power Down Selected
.. 5:4 Reserved
.. 3:2 Forced Active
.. 1:0 Reserved
SF3 Loop Current Status: SF3 is a read only register that stores the current value of the loop current.
.. Units......1.1 Volt
.. Default...00 (no Loop Current Present)
..
Cermetek Microelectronics, Inc XE2422H Surface Mount Modem Module
©2009 Cermetek Microelectronics, Inc. Page 20 Document No. 607-0028 Revision C (10/09)
FCC Instructions
The XE2422H complies with Part 68 of the FCC Rules and Regulations. With each device shipped, there is a label which contains
the FCC Registration Number. The FCC Registration number incorporates the Model Number, Manufacturer Indentifier, Product
Type identifier and Ringer Equivalence Number (REN) for this product. You must, upon request, provide this information to your
telephone company. The format of the FCC Registration Number is shown below.
The mounting of this device in the final assembly must be made in such a manner as to preserve the high voltage protection
between the TIP/RING Connection and the rest of the system. Typically, this may be accomplished by maintaining a minimum
spacing 100 mils between the TIP/RING Traces to the RJ-11C Jack and low voltage portion of the system. No additional circuitry
may be attached between TIP/RING and the telephone line connection, unless specifically allowed in the rules.
The REN is useful to determine the quantity of devices you may connect to a telephone line and still have all of these devices ring
when the number is called. In most, but not all areas, the sum of the RENs of all devices connected to one line should not exceed
five (5.0). To be certain of the number of devices you may connect to the line, as determined by the REN, you should contact the
local telephone company to determine the maximum REN for you calling area.
If your system causes harm to the telephone network, the telephone company may discontinue service temporarily. If possible,
they will notify you in advance. If advance notification is not practical, you will be notified as soon as possible.
Your telephone company may make changes in its facilities, equipment, operations or procedures that could affect proper
functioning of your equipment. If they do, you will be notified in advance to give you an opportunity to maintain uninterrupted
telephone service.
If you experience trouble with this device, please contact CERMETEK at (408) 945-6640 for information on obtaining service or
repairs. The telephone company may ask you to disconnect this device from the network until the problem has been corrected or
until you are sure that the device is not malfunctioning.
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