Tandy DC-2212 User manual

IMPORTANT NOTE!
Your DC-2212 Intelligent Modem is factory preset with the AUTO
ANSWER switch in the OUT position. At power-up, this switch
position provides the "Auto-Dial Mode" which is the proper setting for
most software applications.
Under XENIX, however, this switch must be set to the IN position for
proper operation. (The IN position provides " true carrier detect. " )
Also note that on Xenix versions prior to 3.0, the unattended auto-dial
feature is not supported.

TERMS AND CONDITIONS OF SALE AND LICENSE OF RADIO SHACK COMPUTER EQUIPMENT AND SOFTWARE
PURCHASED FROM A RADIO SHACK COMPANY-OWNED COMPUTER CENTER. RETAIL STORE OR FROM A
RADIO SHACK FRAN C HISEE OR DEALER AT IT S AUTHORIZED LOCATION
LIMITED WARRANTY
I. CUSTOMER OBLIGATIONS
A. CUSTOMER assumes full responsibility that this Radio Shack computer hardware purchased (the " Equipment "), and any copies of Radio
Shack software included with the Equipment or licensed separately (the "So ftware ") meets the specifications, capacity , capabilities,
versatility, and other requirements of CUSTOMER .
B. CUSTOMER assumes full responsib1l1ty for the condition and effectiveness of the operating env ironm ent in which the Equipment and Software
are to function , and for its installation .
11. RADIO SHACK LIMITED WARRANTIES AND CONDITIONS OF SALE
A. For a per i od of ninety (90) calendar days from the date of the Radio Shack sales document received upon purchase of the Equ ip ment . RADIO
SHACK warrants to the original CUSTOMER that the Equ i pment and the medium upon which the Software is stored is free from manufacturing
defects . THIS WARRANTY IS ONLY APPLIC~BLE TO PURCHASES OF RADIO S HACK EQUIPMENT BY THE ORIGINAL CUSTOMER FROM
RADIO SHACK COMPANY-OWNED COMPUTER CENTERS, RETAIL STORES AND FROM RADIO SHACK FRANCHISEES AND DEALERS AT ITS
AUTHORIZED LOCATION . The warranty is void if the Equipment's case or cabinet has been opened. or if the Equipment or Softwa re has been
sub1ected to improper or abnormal use . If a manufacturing defect is discovered during the stated warranty period . the defective Equipmen t
must be returned to a Radio Shack Computer Center . a Radio Shack retail store. participating Radio Shack franchisee or Radio Shack dealer
for repair , along with a copy of the sales document or lease agreement. The original CUSTOMER 'S sole and exclusive remedy in the event of
a defect is limited to the correction of the defect by repair . rep la cement . or refund of the purchase price . at RADIO SHACK 'S election and sole
expense RADIO SHACK has no obligation to replace or repair expendable ite ms .
B. RADIO SHACK makes no warranty as to the des ign, capability , capacity , or suitability for use of the Software , except as provided in this
paragraph . Software is licensed on an " AS I S" basis , without warranty . The original CUSTOMER 'S exclusive remedy, in the event of a
Software manufacturing defect, is its repair or replacement within thirty (30) calendar days of the date of the Radio Shack sales document
received upon license of the Software. The defective Software shall be returned to a Radio Shack Computer Center , a Radio Shack re tail store.
participating Rad io Shack franchisee or Radio Shack dealer along with the sales document.
C Except as provided herein no employee , agent , franchisee . dealer or other person is authorized to g ive any warranties of any nature on behalf
of RADIO SHACK .
D. Except as provided herein . RADIO SHACK MAKES NO WARRANTIES, INCLUDING WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A
PARTICULAR PURPOSE.
E. Some states do not allow li m itations on how long an i mplied warranty lasts . so the above limitation(s) may not apply to CUSTOMER.
Ill. LIMITATION OF LIABILITY
A. EXCEPT AS PROVIDED HEREIN , RADIO SHACK SHALL HAVE NO LIABILITY OR RESPONSIBILITY TO CUSTOMER OR ANY OTHER PERSON
OR ENTITY WITH RESPECT TO ANY LIABILITY , LOSS OR DAMAGE CAUSED OR ALLEGED TO BE CAUSED DIRECTLY OR INDIRECTLY BY
" EQUIPMENT" OR " SOFTWARE " SOLD , LEASED. LICENSED OR FURNISHED BY RADIO SHACK , INCLUDING , BUT NOT LIMITED TO , ANY
INTERRUPTION OF SERVICE . LOSS OF BUSINESS OR ANTICIPATORY PROFITS OR CONSEQUENTIAL DAMAGES RESULTING FROM THE
USE OR OPERATION OF THE " EQUIPMENT " OR " SOFTWARE " IN NO EVENT SH ALL RADIO S HA CK BE LIABLE FOR LOSS OF PROFITS , OR
ANY INDIRECT , SPECIAL , OR CONSEQUENTIAL DAMAGES ARISING OUT OF ANY BREACH OF THIS WARRANTY OR IN ANY MANNER
ARISING OUT OF OR CONNECTED WITH THE SALE . LEASE , LICENSE . USE OR ANTICIPATED USE OF THE " EQUIPMENT " OR " SOFTWARE "
NOTWITHSTANDING THE ABOVE LIMITATION S AND WARRANTIES . RADIO SHACK 'S LIABILITY HEREUNDER FOR DAMAGES INCURRED BY
CUSTOMER OR OTHERS SHALL NOT EXCEED THE AMOUNT PAID BY CUSTOMER FOR THE PARTICULAR "EQUIPMENT" OR " SOFTWARE "
INVOLVED.
B. RADIO SHACK shall not be liable for any damages caused by delay in delivering or furnishing Equipment and / or Software .
C. No action arising out of any claimed breach of this Warranty or transactions under this Warranty may be brought more than two ( 2) years
after the cause of action has accrued or more than four (4) years after the date of the Radio Shack sales document for the Equipment or
Software . whichever first occurs .
D. Some states do not allow the limitation or exc l us i on of incidental or consequential damages , so the above limitation(s) or exclusion(s) may
not apply to CUSTOMER .
IV. RADIO SHACK SOFTWARE LICENSE
RADIO SHACK grants to CUSTOMER a non-exclusive. paid-up license to use the RADIO SHACK Software on one computer . subject to the following
provisions :
A. Excep t as otherwise provided in th is Software License , applicable copyright laws shall apply to the Software .
B. T itle to the med ium on which the Software is recorded (cassette and / or diskette) or stored ( ROM) is transferred to CUSTOMER , but not tit le to
the Software .
C. CUSTOMER may use Software on one host computer and access that Software through one or more terminals if the Software permits this
function.
D. CUSTOMER shall not use , make , manufacture . or reproduce copies of Software except for use on one computer and as is specifically
provided in this Software License . Customer is expressly prohib ited from disassembling the Software .
E. CUSTOMER is permitted to make additional copies of the Software only for backup or archival purposes or if additional copies are required in
the operation of one computer with the Software . but only to the extent the Software allows a backup copy to be made . However . for
TRSDOS Software , CUSTOMER is permitted to make a limited number of additional copies for CUSTOMER 'S own use .
F. CUSTOMER may resell or distribute unmodif ied copies of the Software provided CUSTOMER ha s purchased one coµy of the Software for each
one sold or distributed . The provisions of th is Software License shall also be applicable to third parties receiving copies of the Software from
CUSTOMER.
G. All copyright notices shall be retained on all copies of the Software .
V. APPLICABILITY OF WARRANTY
A. The terms and conditions of this Warranty are applicable as between RADIO S HA CK and CUSTOMER to either a sale of the Equipment and / or
Software License to CUSTOMER or to a transact i on whereby RADIO SHACK sells or conveys such Equipment to a third party for lease to
CUSTOMER .
B. The li mitations of liability and Warranty provisions here in shall inure to the benef it of RADIO SHACK , the author , owner and / or licensor of the
Software and any manufacturer of the Equ ipment sold by RADIO SHACK .
VI. STATE LAW RIGHTS
The warranties granted herein give the original CUSTOMER s pecific legal rights . and the original CUSTOMER may have other rights which vary
from state to state.

The FCC Wants You to Know ...
This equipment generates and uses radio frequency energy. If not installed and used prop-
erly, that is , in strict accordance with the manufacturer's instructions, it may cause interfer-
ence to radio and television reception.
It has been type tested and found to comply with the limits for a Class B computing
device in accordance with the specifications in Subpart J of Part 15 of FCC Rules, which are
designed to provide reasonable protection against such interference in a residential instal-
lation. However, there is no guarantee -that interference will not occur in a particular
installation.
If this equipment does cause interference to radio or television reception, which can be
determined by turning the equipment off and on , the user is encouraged to try to correct the
interference by one or more of the following measures:
• Reorient the receiving antenna
• Relocate the computer with respect to the receiver
• Move the computer away from the receiver
• Plug the computer into a different outlet so that computer and receiver are on different
branch circuits.
If necessary, you should consult the dealer or an experienced radio/television technician for
additional suggestions. You may find the following booklet prepared by the Federal Com-
munications Commission helpful: How to Identify and Resolve Radio-TV Interference
Problems.
This booklet is available from the US Government Printing Office, Washington, DC
20402, Stock No. 004-000-00345-4.
Warning .
This equipment has been certified to comply with the limits for a Class B computing device,
pursuant to Subpart J of Part 15 of FCC Rules. Only peripherals (computer input/output
devices, terminals, printers, etc.) certified to comply with the Class B limits may be attached
to this computer. Operation with non-certified peripherals is likely to result in interference to
radio and TV reception.
In te lligent Mo dem DC-2212 Op eration Manual
©1984 Ta ndy Co rp oration
Fo rt Worth, Texas 76102 U.S.A.
A ll Rights Reser ve d.
Reproduction or use, without express written permission from Tandy Co rpora ti on, of any portion of
this manual is prohibit ed . While reasona bl e e ff orts ha ve been taken in the prepara ti on of this manual
to ass ur e its accuracy, Tandy Co rp ora ti on ass um es no li ability resulting from any errors or omissions
in th is manual, or from the use of the in fo rmation co ntained herein.
IO 9 8 7 6 5 4 3 2

Contents
Getting To Know Your Modem . . . . . . . . . . . . . . .. . . . . . . . . . .. . . . . . . . . . . . . . 3
Setting Up the DC-22I2 Modem ................................... 4
Setting Communications Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Sample Programming Sessions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Log On CompuServe ..................................... ·. 8
Answer or Originate A Call Automatically . . . . . . . . . . . . . . . . . . . . 9
Change Advanced Programming Options . . . . . . . . . . . . . . . . . . . . . 9
Manual Mode Operation ......................................... I0
TRS-XENIX Operation ........................................... II
Wake Up, DC-2212! ................................................... 13
Switching From High to Low Baud Operation ....................... 13
Entering Command Receptive State ................................ 14
Automatic Mode Operations ........................................... 15
Automatic Answer Mode ......................................... 15
Automatic Originate Mode ........................................ 16
Line Status Conditions ........................................... 17
Dial Sequence Emergency Shutdown Command ...................... 18
How To Abort An On-Line Status .................................. 19
Analog Self-Test Mode ........................................... 21
Programming Commands ............................................. 23
Connecting the Modem ............................................... 35
Connecting to the Telephone ...................................... 36
Connecting to a Power Source ..................................... 37
Connecting to Your Computer ..................................... 37

Optional Modem Configurations ....................................... 39
Multi-Line Phone Operation ...................................... 39
RS-232 Protocol Extension ........................................ 39
Synchronous Mode Operation ..................................... 39
'froubleshooting ......................................... , ....... 41
Specifications .............. ' .. ~ .................................. 43
Index ................................................................ 47
Figure 1.
Figure 2.
Figure 3.
Table 1.
Table 2.
Table 3.
Table 4.
Table 5.
List of Illustrations
Front Control Panel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Rear Panel Connections ................................. 35
Connecting the Modem ................................. 36
List of Tables
DC-2212 Programming Commands ........................ 14
Slow Dialing Speed Rate ................................. 26
Fast Dialing Speed Rate .................................. 26
Valid Dialer Digits and Codes ............................. 28
Modem-to-Computer Cables and Connection Points .......... 37
11

Getting to Know Your Modem
Tandy's DC-2212 high speed, intelligent modem has all the features needed to enhance
your data-communications applications -including a data output rate four times faster
than that of the standard "dumb" modem.
This direct-connect, 212-A type modem is not only designed with standard automatic
dial, answer, and disconnect features, but a wide range of system configuration
enhancements as well. After dialing is completed, the DC-2212 modem monitors the
call and reports its progress to your computer over the serial RS-232-C link. These
functions, which are roughly equivalent to the functions of an operator making a call,
include:
• Waiting while the phone rings until the dialed number answers
• Hanging up and redialing later if the number is busy, or if the call has not been
answered after a specified length of time
• Hanging up the handset at the end of a completed call
Each call-progress signal -ring-back, no tone, busy tone, or dial tone -that the
modem detects is printed out as a serial status message on your display. An auto-
disconnect feature permits the modem to disconnect if a carrier signal is not maintained
after a data call has been set up or upon command. This feature is useful in preventing
the tie-up of expensive computer facilities due to wrong-number calls, failure of the
distant party to disconnect from a time-sharing system, or line failures.
All functions of the DC-2212 modem are controlled by ASCII (American National
Standard Code for Information Interchange) encoded commands that you program from
your computer keyboard over the serial RS-232-C interface. For example, you can
control the selection of pulse- or tone-dialing through the dialer programming mode
command, or the number of times the phone is to ring before being answered by using
the advanced programming enable command.
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One of its advanced features is the ability to determine your computer's communications
parameters -baud rate, data bits per word, parity, and stop bits per word -and
adjust its own operation to meet system requirements, using a simple command code
sequence.
Designed with a high degree of intelligence, the DC-2212 allows you to operate your
computer virtually unattended when linked to a telephone -making possible a wide
range of telecommunications applications. Used with the proper applications software
package, the modem is capable of performing operations such as electronic mail and
shopping, central-data-base access, home banking and remote-peripheral sharing.
This manual, in the sections following, will describe how you can use the DC-2212
modem to call (originate) a host computer or information service, or receive (answer) a
call from another computer, either manually or automatically. Additionally, you will
learn how using the modem 's advanced features can actually enhance your
communications applications.
Setting Up the DC-2212 Modem
When you have made the peripheral connections as outlined on page 35, Connecting
the Modem, you are ready to power-up and load your communications software.
When the power is freshly applied, several of the LED indicators on the modem's front
panel will illuminate -and remain lit, depending on the status of the computer's
protocol. These six indicators show the modem's internal and external operation status.
POWER SWITCH
Figure 1. Front Control Panel
4

CD High Speed. Lights when the modem is in high speed (1200 baud)
communications.
@ Off-Hook. Lights when your modem is on-line (connected to the phone lines).
@ Terminal Ready. Lights when the terminal is supplying DTR.
© Carrier Detect. Lights when the modem receives a carrier tone or generates a
false carrier.
® Transmit Data. Lights when the modem is transmitting data.
® Receive Data. Lights when the modem is receiving data.
Your DC-2212 modem permits a computer or terminal to communicate with a remote
computer by converting that computer's electrical signals into audio tones that can be
efficiently handled by the telephone system.
Likewise, the audio tones that the modem receives are converted back to electrical
signals that are understood by the computer.
Setting Communications Parameters
The DC-2212 modem provides data communications in full- or half-duplex mode at
either 0-300 bits-per-second (asynchronous) or 1200 bps (synchronous or
asynchronous). Transmission speed is always selected by the originating modem.
Automatic originate mode operation is a default (preset) condition upon first power-
up. When opened for programming with the auto-baud-rate-detect code (Wake Up,
DC-2212!), the modem automatically synchronizes the baud rate, word length, parity,
and stop-bit numbers of your computer system.
When programmed for automatic answer mode operation, the modem adapts the
communications protocol of the remote computer system upon receipt of a telephone-
line-ringing signal. This auto-answer feature makes it possible for data transmission to
occur between a remote terminal interfaced to a modem and your computer -without
intervention from the operator.
Refer to your computer owner's manual or applications software user's guide if you
require instructions on setting communications parameters.
5

Sample Programming Applications
A Videotex Plus communications package for TRS-80 Model II, 12, and 16
microcomputers is used in the sample programming sessions following. With this
package, you are able to communicate with a variety of information services and host
computer systems. The examples are designed to familiarize you with some of the
operations the modem is capable of performing.
A log-on session gets you started by showing how the modem is used to log on an
information service. The remaining sessio ns demonstrate how you can program the
modem to perform operations, such as dialing your ca ll s and answering the phone
automatically. Additionally, you will learn how the advanced programming options are
used to enhance automatic operations.
Programming the modem . ..
All modem functions are controlled by ASCII encoded commands that you send from
your computer keyboard. A two-key code sequence called the wake-up command is
used to open the modem for programming. (See Wake Up, DC-2212! for an
explanation of the importance of this command 's function, page 13.)
When this two-key code sequence is issued, the DC-2212 automatically adapts the
speed, word length, number bits, and parity of your computer. When answering calls,
the modem adapts to the speed, word length, number bits, and parity of the calling
modem.
l. Check again that all peripherals are correctly connected (C onnecting the Modem
page 35) and receiving power.
2. Flip the power switch on the modem 's front panel to the ON position. Carrier
Detect (CD) indicator lights.
3. Load and run the Videotex Plus communications program as described in your
user's guide.
4. At TR SD 0 S Re ad Y , type l.JI DT Ei< ( ENTER ). Terminal Ready (TR) indicator
lights. The screen show s:
t.!IDTD( 01,00.00
CoPYri9ht 1983 Tandy Corp,
Al 1Ri9hts Rese nied
6