February 2004 0049-0519-500 MD1980C Fast Poll RM Rack-Mount Modem
Contents CHAPTER 1 INTRODUCTION..................................................................................................................3 FEATURES ........................................................................................................................................................4 APPLICATIONS ..................................................................................................................................................4 ANCILLARY DOCUMENTATION .................
Chapter 1 Introduction C ongratulations for purchasing the finest industrial-grade fast-poll rack-mount modem available. The BLACK BOX® MD1980C modem is a 9600/4800/0-1800 bps rack-mount modem designed for 4-wire, full-duplex or 2-wire, half-duplex operation over a voice-band leased line. The modem is designed utilizing the latest digital-signal processing (DSP) technology to achieve high performance.
Features Though functionally similar to commercial modems, the MD1980C provides the following unique features that make it well suited for utility and industrial applications. Requires only one rack slot. Operates over voice-band conditioned or unconditioned leased line and pilot wires. Operates without human intervention, making it ideal for unmanned locations. Works within an extended temperature range of -40ºC to +85ºC.
Ancillary Documentation Ancillary Documentation For information about the Black Box Modem Rack II, refer to the documentation that came with it.
Chapter 2 Installation T his chapter describes how to install the modem. Unpacking Your Hardware Your package should include: At least one BLACK BOX® MD1980C modem This User’s Guide If your package contents are damaged or missing, please contact your place of purchase immediately. Additional Items You Need To use your modem, you need the following additional items: A BLACK BOX® Modem Rack II (p/n RM421A).
Hardware Overview Hardware Overview Front View Figure 2-1 shows a front view of the BLACK BOX® MD1980C modem. Starting from the top, this view shows: A loopback test switch. See page 19. A set of eight LEDs. See page 19. Figure 2-1.
Component View Figure 2-2 shows the component view of the modem. This view shows: Three configuration switch blocks, designated SW1, SW2, and SW3. See page 9. Jumpers located in various positions on the modem. Do not change or remove the straps from these jumpers. Edge connectors at the back of the modem, which plug into the backplane of a BLACK BOX® Modem Rack II (or equivalent rack from Telenetics Corporation or Motorola/UDS).
Configuring the Modem Configuring the Modem You configure the modem using the three sets of DIP switches on the bottom of the modem. , IMPORTANT It is important to follow the three steps described below, in the order shown, to ensure that you configure your modem properly using the modem DIP switches: 1. Use DIP switch 3 (SW3) to configure the modem for your host DTE interface and network topology. Using SW3, you select the modem to operate in high-speed fastpoll or low-speed (FSK) mode. 2.
SW1-1 through SW1-4 − Transmit Level Switches SW1-1 through SW1-4 adjust the modem’s transmit level. Table 2-2 shows the transmit levels you can select using these switches. Table 2-2.
Configuring the Modem SW1-8 − Anti-streaming SW1-8 ON = Anti-streaming active OFF = Anti-stream inactive Typically, anti-streaming is used in multi-point applications to prevent a malfunctioning slave modem from occupying the line indefinitely. When anti-streaming is active, the modem can transmit data for a maximum of 27 seconds before the transmitter turns off automatically. The modem then looks for an ON-to-OFF Request To Send (RTS) transition before proceeding with normal operation.
No provisions for disablement of echo suppressors DTR (circuit 108) is ignored Setting SW2-1 OFF selects Bell 202 mode. SW2-2 Receiver Squelch (FSK Mode 2-Wire Half-Duplex Only) SW2-2 ON = 8ms for Bell 202, 150ms for ITU-T V.
Configuring the Modem When the modem is configured for V.23 operation (SW2-1 ON), the RTS-CTS delay is fixed at 33 ms. SW2-6 FSK CD Delay (Bell 202 Mode Only) SW2-6 ON = 23ms OFF = 6ms SW2-6 selects the FSK CD delay and is valid when Bell 202 mode is active (SW2-1 OFF). Setting SW2-6 ON configures the modem to turn on CD 23 milliseconds after it detects a valid carrier signal. Setting this switch to OFF configures the modem to turn on CD 6 milliseconds after it detects a valid carrier signal.
SW3 DIP Switch Settings SW3 is a 10-position DIP switch. Table 2-5 shows the modem switch settings for DIP switch SW3. A description of the SW3 switch settings follows the table. Table 2-5.
Configuring the Modem Note that DRS controls both the transmitter and receiver. If DRS changes states while the modem is receiving a preamble, data, or a turn-off sequence, the state of the receiver is unknown until the carrier drops and a new preamble is received. We recommend that DRS does not change states until both the local and remote modems’ transmitters are in the idle state. When they are, both the local and remote modems’ DRS signal should change states.
SW3-6 − Reserved (Test Only) SW3-6 Must be OFF SW3-6 must be in the OFF position for normal operation. SW3-7 − 2-/4-Wire Operation SW3-7 ON = 2-Wire, Half-Duplex Mode OFF = 4-Wire, Full-Duplex Mode SW3-7 configures the modem for 4-wire full-duplex or 2-wire half-duplex operation. SW3-8 − Carrier Control SW3-8 ON = Constant OFF = Switched SW3-8 selects either constant or switched carrier.
Installing the Modem Installing the Modem After you set the modem’s configuration switches, you can install it in a slot within a BLACK BOX® Modem Rack II (or equivalent modem rack from Telenetics Corporation or Motorola/UDS). The modem is installed or replaced from the front of the modem cage or modem rack, without disturbing the cable connections on the back. The modem can be installed and removed without having to remove power from the modem cage or modem rack.
Figure 2-4. Modems Installed in the Rack Connecting to a Transmission Line The modem cage or modem rack has different Telco options. Your version may have 16 8-pin modular jack connectors, one for each slot in the modem cage or modem rack. It may also have an optional 50-pin masstermination Telco connector. To connect your modem to a leased line using the modular jack connectors, refer to “Modular Jack Connectors,” below.
LEDs LEDs The front panel of the modem provides the LEDs shown in Table 2-7. Table 2-7. Modem LEDs LED Color Description Power Green Power RTS Yellow Request To Send CTS Yellow Clear To Send TxD Yellow Transmit Data RxD Yellow Receive Data DCD Yellow Carrier Detect ALB Red* Analog Loopback DLB Red* Digital Loopback * When the modem is in remote loopback, both the ALB and DLB LEDs go ON.
Figure 2-6.
Appendix A Troubleshooting I n the event you encounter a problem using your Black Box modem, refer to the troubleshooting information in this appendix. To troubleshoot the power supply and backplane on the modem cage or modem rack, refer to the documentation that came with your modem cage or modem rack. , IMPORTANT If you encounter a problem with your modem, be sure the modem switches are set to the appropriate positions.
Appendix B Specifications General Specifications Data rate: 9600, 4800, or 0-1800 bps asynchronous Data format: 8 or 9 data bits with 1 or more stop bits DTE interface: EIA RS-232 or V.24 compatible Line conditions: TELCO Voice band 4- or 2-wire leased line, conditioned or unconditioned Private metallic circuits up to 9.5 miles (24 AWG) without cable equalizer. Up to 15.
Mechanical Specifications Anti-Streaming: 27-second timer to prevent transmitter lock-up network Mechanical Specifications Dimensions: 9 inches deep x 6.25 inches high x .
Environmental Specifications Operating temperature: -40 to + 85o C Storage temperature: -40 to +125o C Operating humidity: 5 to 95 %, non-condensing.
Appendix C Compliances FCC REQUIREMENTS FOR TELEPHONE-LINE EQUIPMENT 1. The Federal Communications Commission (FCC) has established rules which permit this device to be directly connected to the telephone network with standardized jacks. This equipment should not be used on party lines or coin lines. 2.
Repairs to certified equipment should be made by an authorized Canadian maintenance facility—in this case, your supplier. Any repairs or alterations made by the user to this equipment, or equipment malfunctions, may give the telecommunications company cause to request the user to disconnect the equipment. Users should ensure for their own protection that the electrical ground connections of the power utility, telephone lines, and internal metallic water pipe system, if present, are connected together.
NORMAS OFICIALES MEXICANAS (NOM) ELECTRICAL SAFETY STATEMENT INSTRUCCIONES DE SEGURIDAD 8. Servicio—El usuario no debe intentar dar servicio al equipo eléctrico más allá a lo descrito en las instrucciones de operación. Todo otro servicio deberá ser referido a personal de servicio calificado. 9. El aparato eléctrico debe ser situado de tal manera que su posición no interfiera su uso.
