Omega Speaker Systems VR200 instruction manual Output, Preventing Errors

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6.1 Preventing Errors

Chapter 6 ERRORS DURING RS-422-

AOUTPUT

6.1Preventing Errors

Do not send an FM or LF command from the host PC until the measured data or set point data in all the channels specified by the last command have been output. If an FM or LF command is sent while the VR200 recorder is outputting data, a communication error may occur.

An LF command sent after the TS0 command, or an FM command sent after the TS1 or TS2 command may also cause a communication error.

If an ESC T command was already sent after the last time TS0 was set, data (even in other formats) in any channel at any time interval can be read by the host PC using FM commands as many times as required. At this time (when the FM command is repeatedly sent), the VR200 recorder also sends the data acquired last time ESC T was received.

Also, if an ESC T command was already sent after the last time TS1 or TS2 was set, the settings (even in other formats) in any channel at any time interval can be read by the host PC using LF commands as many times as required.

Thus, once the ESC T command has been sent, the measured values and set values can be read any number of times, which is a very useful function.

Note

When sending data from the host PC to a recorder, use the ESC S command to avoid buffer overflow:

When the VR200 recorder receives an ESC S request, it saves it in the buffer memory. This request is retrieved from the buffer memory and, after acknowledging the command, the recorder sends the status to the PC. Make sure not to send any other commands between sending the ESC S command to the recorder and reading the status from the recorder. This ensures that commands can be received by the recorder since its input buffer is empty.

Example:

10OPEN ”COM1:N81N” AS #1

20‘

30PRINT #1,CHR$(&H1B)+”O 01"

40PRINT #1,”SR01,VOLT,20mV,-2000,2000"

50GOSUB *HANDSHAKE

60PRINT #1,”PS0"

70GOSUB *HANDSHAKE

80PRINT #1,”UD0"

90PRINT #1,CHR$(&H1B)+”C 01"

100CLOSE

110END

120*HANDSHAKE

130PRINT #1,CHR$(&H1B)+”S”; (sending ESC S)

140

LINE INPUT #1,STS$

(reading status)

150

RETURN

 

The command length of the input buffer of the VR200 is 256 bytes for a 4-channel model.

6 ERRORS DURING RS-422-A OUTPUT

6 - 1

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Contents User’sGuide Servicing North America Trademarks PrefaceContents Time Chart Initial Status Errors During RS-422-A Output Transmitting FunctionsProgram Examples Interface Specifications Installing the RS-422-A InterfaceCable Termination Interface Terminal Terminal AssignmentData Configuration Communication WiringText Start-stop Asynchronous CommunicationBuffer Overflow Input BufferSetup Procedure Setting up the RS-422-A Communication InterfaceIdentifier ParametersTerminator Setting the Range and Scale List of Program Set CommandsFormat SRp1,mode Example SR01,SKIPFormat SRp1, mode, p2 Example SR01, DI,Format SRp1, mode, p2, p3, p4, p5, p6, p7, p8 Setting Alarms Setting the Waveform Span Rate TIME/DIV Setting the UnitSetting the Clock Copying the Channel SettingsSetting the Discrete Zone Display Setting the Partial Expanded DisplaySetting the Tag Setting the Data File Name File Setting the Trip LevelSetting the Summer/ Winter Time DST Setting the LCD Brightness and LCD Saver LCDExample MD02, ON, on Format MDp1, p2, p3Alarm Acknowledge List of Program Control CommandsStandard Screen Call Initializing the Data MemorySaving the SET Configuration File Loading the SET Configuration FileSelecting the Output Data Selecting the Output Format for Measured DataMessage Writingfor the VR 200 with style number 2 or higher Execution of Trigger Status OutputRequests for the data to be prepared in the buffer Close Command Open CommandESC O Crlf ESC C CrlfSequence see also Sections 2.3.7 Introduction to Output Data FormatsOutput Data Formats Output Format of Measured Values in Ascii ModeOutput Format of Measured Values in Binary Mode Output Format of Parameter Settings Output Format of Unit and Decimal Point Information Time Chart Initial Status Output Preventing ErrorsESC S CR LF How to Request Error Message OutputTiming of Resetting the Error Status Environment Program ExamplesOpen TEST.DAT for Input AS #2 Others LF is sent automatically 210 ‘ 220 ‘ Open COM11200,N,8,1,LF AS #1 Print a Appendix 1 Ascii Code Table AppendixFile Name Length Appendix 2 File Naming RulesLowercase/Uppercase Letters System-reserved File NamesIndex Index for Command Reference Warrant Y/ Disclaimer Temperature
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