Black Box IC026AE-R2, IC026A-R2 manual Switch SW1 Enabling or Disabling Talk-Back on Terminator

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CHAPTER 4: Controller Operation

1		2	3	4	5	6	7	8		1		2	3	4	5	6	7	8
																				Switch
																				Side
																				Side
																				View
				OPEN										OPEN
				OPEN										OPEN
		Talk-Back on										Talk-Back on
Terminator Disabled										Terminator Enabled

Figure 4-2. Switch SW1: Enabling or Disabling

“Talk-Back on Terminator.”

DOT

When the serial input buffer becomes empty, the interface converter checks the last characters sent to the IEEE bus device. If these were the IEEE bus terminators and Talk-Back on Terminator is enabled, the IEEE bus device is addressed to talk. Any data received by the interface converter from the bus device is sent to the serial host.

When the last IEEE bus terminator is detected from the IEEE device, the interface converter disables the device from sending additional information by asserting Attention (ATN) on the bus.

If the IEEE device does not responded or finish transmission by the time additional characters are received into the serial input buffer, the talk sequence will be aborted to allow additional serial information to be sent to the IEEE device.

The program example on the next page shows how this feature can be used to communicate with a single IEEE instrument. The program example is written in BASIC on an IBM PC or compatible and communicates with a Keithley Model 196 DMM.

10	'
20	'	Example Program using interface converter with
25	'	the Talk-Back on Terminator feature enabled to
30	'	communicate with a Keithley Model 196 DMM
40	'

50' Open BASIC’s serial communications port

60OPEN "COM1: 9600, N, 8, 2" AS 1

70' Set the Model 196 DMM to the 30VDC range

80PRINT #1, "F0R3X"; ' The ; suppresses terminators

90' Request 10 Readings from 196”

100FOR N=1 to 10

110	PRINT #1," " ' Output terminator
120	LINE INPUT #1, A$ ' Get reading from 196

130PRINT A$ ' print it on the screen

140NEXT N

150END

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Contents RS-232↔IEEE Interface Converter RS-232↔IEEE 488 Interface Converter Trademarks Used in this Manual RS-232↔IEEE 488 Interface Converter NOM Statement RS-232↔IEEE 488 Interface Converter Contents RS-232↔IEEE 488 Interface Converter Contents Serial Interface SpecificationsIEEE-488 Interface General SpecificationsDescription IntroductionAbbreviations Serial Port ConfigurationGetting Started InspectionSW3 Serial Port Settings Switch SW1 Selecting the Serial Baud Rate Switch SW1 Selecting the Serial Word Length Data Bits Switch SW2 Selecting the Serial Parity Switch SW1 Selecting the Serial Handshake Selecting Terminator Substitution Switch SW2 Selecting the Serial TerminatorSwitch SW3 Selecting the Ieee Bus Terminator Selecting the ModeSelecting the Ieee Address 10. Switch SW2 Selecting the ModeFeature Selections Serial Interface 15. Selecting RS-232 or RS-422 Signal Levels Request To Send-Output-Pin RxD Receive Data-Input-PinTxD Transmit Data-Output-Pin Clear To Send-Input-Pin+TxD Transmit Data Plus-Output-Pin Vtest Test Voltage-Output-PinGnd Ground-Pin +RxD Receive Data Plus-Input-PinRTS CTS DSR RTS CTS GeneralGetting Started Controller-Mode Serial to Ieee Operation Controller OperationSerial and Ieee Terminator Substitution Ieee Address Selection Talk-Back FeaturesSwitch SW1 Enabling or Disabling Talk-Back on Terminator Switch SW2 Enabling or Disabling Talk-Back on Timeout SP1PA1000,1000PDPA1000,6000PUSP0 7470APlotter Applications A PC-Based Graphics System SW3 MacPlot Configuration Screen Setting the Internal DIP Shorting Jumper for RS-422 SW3 Printer Applications Serial and Ieee Input Buffers Peripheral OperationPeripheral-Mode Operation Ieee Data Transfers Controlled BUS Data Transfers DIO8 Ieee Input Buffer not Empty Serial-Poll Status-Byte RegisterIeee Input Buffer Full RsvNot Defined-Always Serial Input Buffer not EmptyIeee 488 Bus Implementation Use of Serial and Bus TerminatorsUntalk UNT SW3 View for Ieee Address Selection General Structure Ieee 488 PrimerHistory RS-232↔IEEE 488 Interface Converter DMM Send It to My AddressBus Management Lines Data Valid DAV Handshake LinesData Lines Multiline CommandsTalk Address Group TAG More on Service Requests Serial Poll Address Device Part Number Function Theory of OperationComponent Layout of the Interface Converter’s Motherboard Board LayoutRED BLK CLS Appendix A. Sample Dumb-Terminal ProgramSOH Multiline MessagesAscii Character How To Read the ChartDIO1 DIO2 DIO3 IndexIndex SW1 Copyright 1998. Black Box Corporation. All rights reserved