Campbell COM220 User manual

COM220 Telephone Modem
Revision: 4/12
Copyright © 1997-2012
Campbell Scientific, Inc.

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COM220 Telephone Modem
Table of Contents
PDF viewers: These page numbers refer to the printed version of this document. Use the
PDF reader bookmarks tab for links to specific sections.
1. Introduction..................................................................1
1.1 General Description ..................................................................................1
1.2 Computer Requirements ...........................................................................2
2. Specifications ..............................................................3
3. Installation....................................................................3
3.1 Connecting to Datalogger .........................................................................3
3.2 Connecting to Earth Ground.....................................................................5
3.3 Telephone to MD485 or Telephone to RF Systems..................................6
3.4 Telephone Service ....................................................................................6
3.5 Connecting to a Surge Protector ...............................................................6
4. Modem Settings ...........................................................8
5. Troubleshooting ..........................................................9
Appendices
A. Changing COM220 Settings ................................... A-1
A.1 DIP Switch Settings ............................................................................ A-1
A.2 Hayes AT Commands......................................................................... A-2
A.3 Downloading a New Operating System to the COM220.................... A-6
A.4 Program Examples.............................................................................. A-7
A.4.1 ModemCallback Example (for CR1000) .................................. A-7
A.4.2 DialModem Example (for CR1000).......................................... A-8
A.4.3 P97 Instruction (for CR10X)..................................................... A-9
A.4.4 Example Programs for Data-Callbacks via a CR1000
Datalogger Router .............................................................. A-11
B. CS I/O Connection................................................... B-1
B.1 CS I/O 9 Pin Connection......................................................................B-1
C. Theory of Operation................................................ C-1
C.1 Theory of Operation.............................................................................C-1
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COM220 Telephone Modem Table of Contents
ii
D. FCC Warning to Users of
Class A Computing Devices..............................D-1
E. IC Information .......................................................... E-1
List of Figures
1. COM220 DIP switches. Five screws and the outer cover must be
removed for access to the DIP switches.................................................. 1
2. COM220 .................................................................................................... 2
3. CR1000 and COM220 using remote telephone line .................................. 4
4. CR10X with CR10 wiring panel and COM220 using RJ11C telephone
jack.......................................................................................................... 5
5. Top view of surge suppressor wiring......................................................... 7
6. Side view of surge suppressor wiring ........................................................ 8
A-1. COM220 to computer connection...................................................... A-3
A-2. Device Configuration screen ............................................................. A-4
A-3. Terminal Emulator screen in Device Configuration .......................... A-5
A-4. Send OS Screen in Device Configuration.......................................... A-7
B-1. CS I/O pin out .................................................................................... B-1
List of Tables
1. Dataloggers that Require Direct 12 VDC Connection to COM220........... 4
A-1. Selecting ME Baud-rates via DIP Switches 3 and 4.......................... A-2
A-2. Maximum Datalogger ME Baud-rate ................................................ A-2

COM220 Telephone Modem
1. Introduction
1.1 General Description
The COM220 modem is a selectable-baud-rate modem employing the Hayes
AT command set. Its primary use is as a remote site phone modem connected
to a CSI datalogger. The modem is powered and enabled by the battery-
powered datalogger. When not active, the COM220 draws 100 to 120 μA
from the datalogger’s 12 VDC output. During a call, it draws about 30 mA.
The COM220 is a replacement for the COM210. However, the COM220
supports both synchronous device communication (SDC) and modem enable
(ME) communication, as well as various ME baud rates (9600 to 115200).
The default settings for the COM220 at shipping are SDC7, and PakBus ready
(see Appendix A for details).
The default settings ARE NOT compatible with dataloggers
that have non-PakBus operating systems (e.g., CR510,
CR10X, CR23X, CR7, CR5000). However, compatibility
with non-PakBus dataloggers is easily achieved by
changing DIP switch settings (Figure 1). If you want to use
the COM220 as a drop-in replacement for the COM210,
the COM220 settings should be changed to modem enable
(DIP switch 1 open), and 9600 baud (DIP switches 3 and 4
open). Instructions for configuring the COM220 are
described in Appendix A.
IMPORTANT
FIGURE 1. COM220 DIP switches. Five screws and the outer cover must
be removed for access to the DIP switches.
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COM220 Telephone Modem
The COM220 is connected to a CSI datalogger by a 9-pin subminiature D
cable. This is the same 9-pin CS I/O interface common to all Campbell
Scientific dataloggers (except the CR200 series). This is not an RS-232
connection. Appendix B describes the CS I/O interface.
The COM220 can be used as an originate modem at the datalogger site. For
newer Pakbus dataloggers (e.g., CR800, CR1000, CR3000) use the
ModemCallback instruction or the DialSequence and DialModem instructions
to program the datalogger to originate a call to the computer. For non-Pakbus
dataloggers (e.g., CR510, CR10X, CR23X), and for older PakBus dataloggers
(e.g. CR10XPB, CR23XPB, CR510PB) use Instruction 97 to program the
datalogger to originate a call to the computer. Refer to your datalogger manual
and LoggerNet Help files for detailed descriptions of these instructions. In
addition, Appendix A.4 includes sample programs for the ModemCallback,
DialModem, and P97 instructions.
The COM220 features a built-in speaker to allow monitoring of calling and
connection. See Appendix A.2 for the Hayes AT commands that affect the
speaker on/off and volume settings.
FIGURE 2. COM220
1.2 Computer Requirements
A Hayes-compatible modem is used at the computer site with Campbell
Scientific computer software to call the datalogger attached to the COM220.
The computer’s modem must be configured to the proper settings using a set of
modem initialization strings in the software program’s pick list.
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COM220 Telephone Modem
2. Specifications
Standards: V.92, K56Flex, V.90, V.34, V.32bis, V32,
V23, V22bis, V22, V.21, B212, B103
Registration: FCC US: 3A4M508BSM2-T-W
IC 2377 A-SM2TW
TBR21
Operating voltage: 12 VDC
Current drain: 100 to 120 μA quiescent; 30 mA active
Communication rate between
datalogger and COM220: 9600, 38400, 57600, 115200 bps (selected
by user)
Operation: Full-duplex over standard analog phone
lines
Operating temperature: -25° to +50°C std, -40° to +85°C optional
Dimensions: 16.5 x 2.5 x 6.6 cm (6.5 x 1.0 x 2.6 in)
Weight: 0.16 kg (0.35 lbs)
3. Installation
The COM220 is designed to be used with standard analog telephone lines. It
will not work with a digital telephone line. Connection to telephone-company-
provided coin service (central office implemented systems) is prohibited.
Connection to party line service is subject to state tariffs.
3.1 Connecting to Datalogger
Connect the cable from the telephone RJ11C jack to the modem as shown in
Figure 4. If the telephone company has not installed surge protection in the
telephone line (no RJ11C jack), one must install surge protection (CSI item
number 6362 or 4330) and connect the ring and tip terminal blocks as shown
in Figure 3.
Current Campbell Scientific dataloggers provide 12 VDC to the COM220 from
the CS I/O port via the SC12 cable (Figure 2). Older dataloggers do not
provide 12 VDC on their CS I/O port. When used with the older dataloggers
listed in Table1, 12 VDC and ground need to be connected via the green power
connector on the side of the COM220 (see Figure 4).
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COM220 Telephone Modem
TABLE 1. Dataloggers that Require Direct
12 VDC Connection to COM220
CR10(X) with silver wiring panel
CR10(X) with black CR10 wiring panel (P/N
8032)
21X(L)—serial number 13,442 or lower
CR500⎯serial number 1764 or lower
CR7—700X serial number 2778 or lower
SE 12 34 56 78
H
1234
L
DIFF
H
EX1
HLHLL
P2
P1
12VG
DC ONLY
CAUTION
LUG
GROUND
POWER IN
WIRING PANEL
CR1000
PERIPHERAL PORT
RS-232 (Not Isolated)
SN:
CS I/O
MADE IN USA
11
109
SE 15 1613 1412
H
L
DIFF
H
EX2
HLHLL
EX3
5678
SW-12
5V 12V 12V
C5 C4 G G G G C1 C2 C3 G G
C6 C7 C8
Tx
COM1
Rx Tx Rx Tx Rx Tx Rx
COM2 COM3 COM4
POWER OUT
SDM
G 12V
Burial Phone Cable
Blue = Ring
Blue/White = Tip
Phone Line
Transient Protector
(Model 6362 or 2372-01)
SC12 Cable
Earth
Ground
FIGURE 3. CR1000 and COM220 using remote telephone line
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COM220 Telephone Modem
CAMPBELL
SCIENTIFIC
INC.
CR10
MADE IN USA
WIRING PANEL NO.
EARTH
DIFF
SE
AG H L AG H L AG H L AG GGE3 AG
4 5 6
78 910 1112
GGGG
12V 12V
SWITCHED
12V
G12V
POWER
IN
SERIAL I/O
SE
DIFF AG H L AG H L AG H L AG GGE1 E2
1 2 3
12 34 56
G 5V5V P1 P2 C8 C7 C6C5C4C3C2 C1
CONTROL
12V
SWITCHED
To Earth
Ground
14 AWG Ground Wire
SC12 Cable
Telephone Wall
Jack
Red Black
(Ground)
(+12v)
FIGURE 4. CR10X with CR10 wiring panel and COM220 using RJ11C
telephone jack
3.2 Connecting to Earth Ground
Connect the green 14 awg grounding wire (provided with the COM220) to the
ground terminal (GND) on the COM220 and to the enclosure’s earth ground
connection. If the site does not have a grounded enclosure, then connect the
ground wire directly to an earth ground connection. The datalogger ground
should also be tied to the earth ground (see Figures 3 and 4).
The modem must be grounded for its transient protection
to work.
CAUTION
5

COM220 Telephone Modem
3.3 Telephone to MD485 or Telephone to RF Systems
Telephone to MD485 or telephone to radio configurations can be utilized for
communicating with multiple dataloggers through one telephone line. For
telephone to MD485 or telephone to radio communications (with no datalogger
router), the COM220 should be set for ME mode. The COM220 and MD485
should be set to the same baud rate. When using a PakBus network with a
datalogger configured as a router, the COM220 can be set for SDC7 and the
radio for SDC8, or vice versa. Contact a Campbell Scientific Applications
Engineer for more information. In addition, Appendix A.4.4 includes example
programs for both a router datalogger and a remoter datalogger communicating
by telephone to MD485 or telephone to radio.
3.4 Telephone Service
The goal of the telephone company is to provide you with the best service it
can. In order to do this, it may occasionally be necessary for them to make
changes in their equipment, operations, or procedures. If you have any
questions about your telephone line, such as how many pieces of equipment
you can connect to it, the telephone company will provide this information
upon request. If the telephone company requests information concerning the
equipment which you have connected to your telephone line, the FCC
registration number and the ringer equivalence number (REN) of the COM220
are listed on its label. Additional technical information from the FCC and IC
on the COM220 is available in Appendices D and E, respectively.
If the local telephone company does not provide phone-line
surge protection, a Campbell Scientific surge suppressor should
be used. Refer to Section 3.5 for more information.
NOTE
3.5 Connecting to a Surge Protector
Campbell Scientific offers two surge protectors (CSI model 4330 and CSI
model 6362). The 4330 and 6362 are essentially the same, except the 6362 has
hardware for mounting to an enclosure backplate.
The 4330 is also known as the 2374-01.
NOTE
The 4330 and 6362 have a protector element for each line that consists of a
heavy-duty-rated, two-element gas tube, an external backup gap assembly, and
a switch-grade shorting mechanism. The gas tubes (tip and ring) are sealed in
a fire-resistant plastic body. DC Breakdown @ 100 V/sec is 300 to 500 volts;
DC extinguishing @ 52 V, 135 V, and 150 V is less than 150 milliseconds.
Figures 5 and 6 show the wiring for connecting the surge suppressor. Color
coding of wires may vary. The important consideration is to follow TIP all the
way through and RING all the way through. Getting wires crossed typically
does not damage anything. The phone line just will not work until the wires
are straightened out.
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COM220 Telephone Modem
Phone wires are live, typically with low voltage (24 Vdc).
While not harmful in most situations, Campbell Scientific
recommends installing the surge protector in dry weather
only by technicians with a healthy heart.
CAUTION
FIGURE 5. Top view of surge suppressor wiring
7

COM220 Telephone Modem
FIGURE 6. Side view of surge suppressor wiring
4. Modem Settings
The COM220 is shipped from the factory with default settings that support
PakBus dataloggers (e.g., CR800, CR1000, CR3000, CR10XPB). The modem
comes configured for Synchronous Device Communication (SDC7), and if
using a PakBus datalogger, can answer a call as soon as a call is detected.
Default settings must be changed if using a non-PakBus datalogger.
The default settings ARE NOT compatible with dataloggers
that have non-PakBus operating systems (e.g., CR510,
CR10X, CR23X, CR7, CR5000). However, compatibility
with non-PakBus dataloggers is easily achieved by
changing DIP switch settings (Figure 1). If you want to use
the COM220 as a drop-in replacement for the COM210,
the COM220 settings should be changed to modem enable
(DIP switch 1 open), and 9600 baud (DIP switches 3 and 4
open). Instructions for configuring the COM220 are
described in Appendix A.
IMPORTANT
You can modify the following COM220 settings with DIP switches:
1) Communication mode (e.g., SDC or Modem Enable)
2) ME baud rate
3) PakBus ready
Additional changes (see examples below) may be modified with Hayes AT
commands. Appendix A.2 describes the procedures and commands required to
effect the changes described in this section.
8

COM220 Telephone Modem
Some of the AT command settings one may change are:
Disable auto-answer: This option is used only when the modem is not to
answer a call. For example, the COM220 is connected to a telephone line that
is to be used part time for voice communication. In this situation it is best to
have the datalogger call the computer.
Speaker On/Off and Volume: Default settings have the speaker on only
during call establishment and set to a low volume. The speaker may be turned
completely off in order to limit the current drain during the connection or so
you don’t hear the speaker. It is also possible to set the speaker volume higher,
if you want to hear the speaker better than the default low volume setting.
Answer on Xth ring: This option is used when the modem is sharing a line
and you only want it to answer after a specified number of rings. For example,
the COM220 is sharing a line with people at an office. It can be programmed
to only answer after the third ring. If the PC calls when the office is closed and
no one answers the phone after three rings, the datalogger will pick it up.
Change telephone system types: Change from the Bell 212A (U.S. and
Canada) system to a CCITT V.32 (foreign, 9600 baud) or CCITT V.22
(foreign, 1200 baud) system. This does not mean that the COM220 is tested
and approved for all foreign countries.
CITT is an international consultative committee that sets international
communications usage standards. V.32 and V.22 are CCITT standards that the
COM220 meets.
5. Troubleshooting
When the Campbell Scientific software cannot establish a link to a remote
datalogger that is connected to a COM220, check the following:
1) Verify that the modem initialization settings on your computer are correct
for your specific calling modem (i.e., the modem attached to your
computer). See the calling modem’s software manual and/or help screens
for more information.
2) If using a non-PakBus datalogger (e.g., CR510, CR10X, CR23X, CR7,
CR5000), verify that DIP switch 1 on the COM220 is in the OPEN
(modem enable) position. For PakBus loggers (e.g., CR800, CR850,
CR1000, CR3000, CR10XPB, 23XPB, etc.), DIP switch 1 can be in either
position, but closed (SDC7) is preferred. See Appendix A.1 for details.
3) If the COM220 is set for Modem Enable (DIP switch 1 open), verify that
the ME baud rate selected (switches 3, 4) agrees with related
communication instructions in the datalogger program. Instructions for
setting the COM220’s ME baud rate are found in Appendix A.1.
4) If the COM220 is set for Modem Enable (DIP switch 1 open) and you are
unable to connect to the datalogger, try setting the datalogger BaudrateME
to a negative number (e.g. -9600) in order to enable auto-bauding in the
datalogger. If the datalogger BaudrateME is positive (due to an earlier
program instruction or Status Table configuration) the datalogger will be
9

COM220 Telephone Modem
unable to communicate with the COM220 unless baud rates happen to
match. A good rule of thumb is to keep baud rates negative (-) in
programs and when configuring the Status Table to allow datalogger
auto-bauding.
5) If unable to connect to a datalogger via the COM220, make sure that the
datalogger is not beaconing to the same port for which the COM220 is
configured (e.g., if the COM220 is configured for SDC7 and the
datalogger's BeaconSDC7 is set to something other than 0, then a
connection cannot be established).
6) If the COM220 is in Modem Enable mode, verify that the COM220 is the
only Modem Enable device connected to the datalogger. Other common
Campbell Scientific modem enable devices are the SC32B, some RF
modems, the MD485, the RF401, the SC932A, and the PDA-to-CS I/O
connector.
7) If the COM220 is in SDC mode (the default is SDC7, with DIP switch 1
closed and DIP switch 2 open), verify that any other SDC devices attached
to the datalogger are using a different SDC address (e.g., if the COM220
is configured for SDC7, another SDC device attached to the datalogger
must use SDC8).
8) Verify that no other software application is currently using the same COM
port on the computer. Even if a program is minimized in windows, it may
put a lock on a COM port. Some notebook computers do not
automatically activate the COM ports. Verify that the COM port you are
using is activated.
9) Use the Low Level Log in the Campbell Scientific software, LoggerNet,
[under Status Monitor, Tools, Log Tool, Options, View Low Level Log
(I/O)] to see connection progress as a link is being established. Assuming
the above items are O.K., the Low Level Log will display
“ATDT#######”. Where #### is the phone number entered in LoggerNet
Setup’s Phone Remote for the datalogger you are trying to call. The
modem attached to the computer will respond back to the computer with
result codes showing how the call is progressing. These responses should
include “RING” and “CONNECT ####” where #### is the negotiated
modem-to-modem connection baud rate. The maximum baud rate setting
in Setup’s PakBusPort [LoggerNet, Setup, PakBusPort (in the device
map)] may limit the baud rate selected by the modems since it defaults to
9600. You can sometimes achieve a higher connection baud rate by
raising the PaKBus Port’s maximum baud rate.
10) Can you attach a normal analog telephone to the line and make a call out?
If not, contact your local telephone company. If you can make a call out
but the connection is poor or faint, contact your local telephone company.
11) Verify the COM220 is receiving 12 VDC. If the COM220 is receiving 12
VDC from a separate power supply instead of the datalogger, is the ground
of the separate power supply connected to the datalogger’s ground?
12) Verify the datalogger is turned on.
10

COM220 Telephone Modem
To comply with FCC rules and regulations, all repairs on the COM220 modem
must be performed by Campbell Scientific, Inc. or an authorized agent of
Campbell Scientific, Inc. For assistance in installation, troubleshooting, or for
repair, contact Campbell Scientific:
Campbell Scientific, Inc.
815 West 1800 North
Logan, Utah 84321-1784
Telephone: [phone]
Fax: [phone]
Web site: www.campbellsci.com
11

COM220 Telephone Modem
12

Appendix A. Changing COM220
Settings
Changing any of the modem's settings may result in
communication problems. After changing the settings, try
the modem locally before installing it at a remote location.
To speed problem resolution when contacting Campbell
Scientific for support, please inform us of any modem
setting changes that have been made.
CAUTION
A.1 DIP Switch Settings
The following COM220 settings are changed by opening or closing DIP
switches:
1) Communication mode, either Synchronous Device Communication (SDC)
or Modem Enable (ME)
2) ME baud-rate
3) PakBus ready.
To change DIP switch settings, the outer cover must first be removed by
unscrewing and removing the five Philips head screws on the cover.
It is necessary to cycle power to the COM220 for changes
to the DIP switch settings to take effect. This is done by
removing the 9 pin connector for about 5 seconds. As with
other devices, if you leave the power off for too short a
time, you may get unexpected results.
IMPORTANT
DIP Switches 1 and 2: SDC or Modem Enable
The COM220 supports Synchronous Device Communication (SDC) and
Modem Enable (ME) communication. Switch 1 selects between SDC and ME.
If switch 1 is open, ME mode is selected. If switch 1 is closed and switch 2 is
open (default), SDC7 is selected. If both switch 1 and 2 are closed, SDC8 is
selected. SDC is not supported by non-Pakbus operating systems (e.g.,
CR10X, CR23X, CR7, CR510). Hence, to connect with these older
dataloggers, switch 1 must be open (i.e., Modem Enable mode selected).
DIP Switches 3 and 4: ME Baud-rates
DIP switches 3 and 4 only have effect when the COM220 is in Modem Enable
mode. If the COM220 is in ME mode, switches 3 and 4 select the baud-rate
setting between the COM220 and the datalogger as follows:
A-1

Appendix A. Changing COM220 Settings
TABLE A-1. Selecting ME
Baud-rates via DIP Switches 3 and 4
ME Baud-rate Switch 3 Switch 4
9600 Open Open
38400 Open Closed
57600 Closed Open
115200 Closed Closed
Please note that older dataloggers (e.g. CR10X, CR23X, CR510) cannot
support the highest COM220 ME baud-rates. Table A-2 lists maximum
datalogger baud-rates.
TABLE A-2. Maximum Datalogger ME Baud-rates
Datalogger Max Baud-rate
CR10X, CR510, CR7, CR21X 9600
CR23X 38400
CR5000 57600
CR800, CR1000, CR3000 115200
DIP Switches 5, 6, and 7: Not used
DIP Switch 8: Configuration Mode
Closing DIP switch 8 (and cycling power to the COM220) places the COM220
in configuration mode. The COM220 can be configured using an SC532 or an
SC532A with a 12V AC adapter (part number 15966) and Device
Configuration utility ver 1.6 or newer and Hayes AT Commands (see below).
A.2 Hayes AT Commands
In order to configure the COM220 with Hayes AT commands, you will need
the Campbell Scientific Device Configuration utility ver 1.6 or newer and a
SC532 or SC532A device. An SC12 cable must be connected to the peripheral
port on the SC532 or SC532A and the CS I/O port on the COM220. Another
cable should connect the “RS232” port (if using an SC532 device) or the “PC”
port (if using an SC532A device) to one of your computer's serial ports. If
using an SC532A device, power will be provided to the modem by the SC532A
with a 12V AC adapter (Figure A-1). However, if using the older SC532, you
must apply 12 V to the COM220 via the green connector.
A-2