Motorola MVME197LE user manual EIA-232-D Interconnections

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EIA-232-D INTERCONNECTIONS

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The EIA-232-D Standard is the most widely used interface between terminals and computers or modems, and yet it is not fully understood. This is because all the lines are not clearly defined, and many users do not see the need to conform for their applications. A system should easily connect to any other. Many times designers think only of their own equipment, but the state-of-the- art is computer-to-computer or computer-to-modem operation.

The DIA-232-D Standard was originally developed by the Bell System to connect terminals via modems. Therefore, several handshaking lines were included. In many applications these are not needed, but since they permit diagnosis of problems, they are included in many applications.

Table A-1 lists the standard DIA-232-D interconnections. To interpret this information correctly it is necessary to know that EIA-232-D is intended to connect a terminal to a modem. When computers are connected to computers without modems, one of them must be configured as a terminal and the other as a modem. Because computers are normally configured to work with terminals, they are said to be configured as a modem. Also, the signal levels must be between +3 and +15 volts for a high level, and between -3 and -15 volts for a low level. Any attempt to connect units in parallel may result in out of range voltages and is not allowed by the EIA-232-D specifications.

MVME197LE/D2A-1

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Contents MVME197LE/D2 MVME197LERestricted Rights Legend Document Terminology PrefaceBIT Document Title Motorola Publication Number Related DocumentationPage Page Safety Summary Safety Depends on YOU Contents Appendix a List of Figures Xii List of Tables Xiv General Description IntroductionOte FeaturesSpecifications MVME197LE SpecificationsCharacteristics Specifications Cooling Requirements FCC Compliance Equipment RequiredSupport Information Hardware Preparation Unpacking InstructionsHardware Preparation and Installation VMEbus Connector P1 Configuration Switches Switch S1Configuration Switch S1 General Information S1-1 to S1-8 OFF -- All Ones Factory Configuration Installation Instructions Switch S6Connectors MVME197LE Module Installation System Considerations MVME197LE/D2 Hardware Preparation and Installation Controls and Indicators Abort Switch S2Reset Switch S3 Front Panel Indicators DS1-DS6 Memory MapsProcessor Bus Memory Map Processor Bus Memory Map Local Devices Memory Map Address Range Devices Accessed Port SizeDetailed I/O Memory Maps 100 BusSwitch Register Memory Map108 110Memory Maps ECDM0 ECDM1 ECDM2 ECDM3 ADDR/REGISTER Ecdm CSR Register Memory MapDcam I2C Register Memory Map Dcam I2C Base Address = $C0 default OffsetOperating Instructions Offset VMEchip2 Memory Map Sheet 1Operating Instructions VMEchip2 Memory Map Sheet 2 Global Access BUS Watchdog Timeout Prescaler AdjustOperating Instructions VMEchip2 Memory Map Sheet 3 Operating Instructions VMEchip2 Gcsr Base Address = $FFF40100 VMEchip2 Memory Map Sheet 4Operating Instructions PCCchip2 Memory Map Printer SEL Interrupt Control Register $FFF42032 Printer Fault Interrupt Control Register $FFF42031Printer PE Interrupt Control Register $FFF42033 Printer Busy Interrupt Control Register $FFF42034Cirrus Logic CD2400 Memory Map Offsets Size Access Cirrus Logic CD2401 Serial Port Memory MapBase Address Is $FFF45000 Data Bits Address D31 D16 D15 11 C710 Scsi Memory Map Accesses may be 8-bit or 32-bit, but not 16-bit12. MK48T08 BBRAM, TOD Clock Memory Map Address Range Description Size Bytes13. Bbram Configuration Area Memory Map 14. TOD Clock Memory MapData Bits Address Function BBRAM, TOD Clock Memory Map 0460000000470476 VMEbus Memory Map VMEbus Accesses to the Local Peripheral Bus01-W3869B03A 5000Local Reset Operation Software InitializationMulti-MPU Programming Considerations User’s Manual MVME197LE Functional Description Data Bus StructureMC88110 MPU Functional Description MC88110 Address Data MUX Address Bus Data Bus 256 BusSwitchMezzanine Address Bus Memory ArrayBattery Backup RAM and Clock Flash MemoryOnboard Dram VMEbus Interface InterfacesSerial Port Interface Ethernet Interface Printer InterfacePeripheral Resources Programmable Tick TimersScsi Interface Scsi TerminationProcessor Bus Timeout Watchdog TimerLocal Peripheral Bus Timeout Interrupt SourcesMVME197LE/D2 Functional Description EIA-232-D Interconnections Table A-1. EIA-232-D Interconnections Pin Signal Signal Name and Description Number MnemonicRing Indicator RI is sent by the modem to User’s Manual Figure A-1. Middle-of-the-Road EIA-232-D Configuration Figure A-2. Minimum EIA-232-D Connection Numerics IndexIN-2 IN-3 Index

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