background image

November 1985

 National Instruments

The following table shows what each LED indicates when lit.

POWER

READY

TALK

LISTEN

ATN

indicates power is on.

indicates that the power-on self-test has passed
successfully and unit is ready to operate.

indicates that the GPIB-MAC is currently
addressed to Talk on the GPIB.

indicates that the GPIB-MAC is currently
addressed to Listen on the GPIB.

indicates that the GPIB signal line ATN* is
asserted (low).

indicates that the GPIB signal line SRQ* is

asserted (low).

The Model GPIB-MAC Back Panel.

The 

back panel of the GPIB-MAC is shown in the following figure.

The power connector, 

 configuration switch, 

 

subminiature connector, and GPIB (IEEE-488) port are shown.

4

 ONE   INTRODUCTION

Содержание GPIB-MAC

Страница 1: ...uments Model GPIB MAC User Manual Part Number 320064 01 November 1985 Edition National Instruments 12109 Technology Boulevard Austin Texas 78727 512 250 9119 Copyright 1985 by National Instruments All Rights Reserved ...

Страница 2: ...ning the part to the owner All items returned to National Instruments for repair must be clearly marked on the outside of the package with a RMA No other warranty is expressed or implied National Instruments shall not be liable for consequential damages Contact National Instruments for more information IMPORTANT NOTE The material in this manual is subject to change without notice National Instrume...

Страница 3: ...in which case the user at his own expense will be required to take whatever measures may be necessary will be required to take whatever measures may be necessary to correct the interference If the equipment does cause interference to radio or television reception which can be determined by turning the equipment on and off one or more of the following suggestions may reduce or eliminate the problem...

Страница 4: ...plug Replace the GPIB cable with Hewlett Packard Model 10833 cable If none of these measures resolves your interference problems contact the manufacturer or write to the U S Government Printing Office Washington D C 20402 for the booklet How to Identify and Resolve Radio TV Interference Problems Stock Number 004 000 000345 4 ...

Страница 5: ...ration of the GPIB For more specific details on the operation of the GPIB refer to the IEEE Std 488 1978 IEEE Standard Digital Interface for Program mable Instrumentation Whatever your level of experience if you encounter problems National Instruments has a staff of applications engineers ready to help you with your particular problem Just call 800 53 l GPIB 800 531 5066 outside Texas 800 IEEE 488...

Страница 6: ...ion The function descriptions are arranged in alphabetical order and each contains the syntax and purpose of the functions and examples contains a table of multiline interface messages lists status information shows how to change the operating voltage from 115 to 230 describes the operation of the GPIB gives answers to common questions explains the use and operation of Parallel Polls gives additio...

Страница 7: ...ion Installation 7 Voltage Requirements Configure the GPIB MAC Rear Panel Switches Switches 1 and 2 Factory Use Only 9 Switch 3 Word Length 10 Switch 4 Stop Bits 11 Switches 5 and 6 Parity Type 12 Switches 7 8 and 9 Baud Rate 14 Connect Cables 15 Turn Power Switch to On 17 SECTION THREE Programming the GPIB MAC 17 Programming Messages 17 Programming Message Format 18 How Messages are Processed 18 ...

Страница 8: ...Controller to Standby id MAC Identify System ist Set or Clear Individual Status Bit lot GotoLocal on1 Place the GPlB MAC Online Offline pet Pass Control ppc Parallel Poll Configure ppu Parallel Poll Unconfigure rd Read Data rpp Request Conduct a Parallel Poll rsc Request or Release System Control rsp Request Conduct a Serial Poll rsv Request Service Set or Change Serial Poll Status Byte sic Send I...

Страница 9: ...tem Controller and Active Controller 109 GPIB Signals 110 Data Lines 110 Handshake Lines 111 Interface Management Lines 111 Physical and Electrical Characteristics 114 Configuration Restrictions 115 APPENDIX E Common Questions 117 APPENDIX F Parallel Polling Operation Configuration 119 The Parallel Poll 119 Disabling Parallel Poll Response 119 Example 121 APPENDIX G Setting Switches 123 APPENDIX H...

Страница 10: ...ts 124 Programming Steps 124 Step 1 stat Function 125 Step 2 Serial Port Functions 125 Step 3 GPIB Initialization Functions 125 Step 4 Communicate with rd and wrt Functions 127 APPENDIX I Serial Port Sample Program xii TABLE OF CONTENTS ...

Страница 11: ...tory Use Only 9 7 bit Word Length 9 8 bit Word Length 10 1 Stop Bit 10 2 Stop Bits 11 Configuration for Parity Types 12 Baud Rate Settings 14 GPIB MAC with Serial Cable Power Cable and GPIB Cable APPENDIX C Changing from 115 Volts AC to 230 Volts AC 105 GPIB MAC with Cover Removed APPENDIX D Operation of the GPIB 109 GPIB Cable Connector 112 Linear Configuration of GPIB Devices 113 Star Configurat...

Страница 12: ...23 Bus Management Functions 23 GPIB Initialization Functions 24 Serial Poll Functions 24 Low level Controller Functions 24 Parallel Poll Functions 25 Serial Port Initialization Functions 25 General Use Functions 25 GPIB MAC Functions SECTION FOUR Functions 39 Data Transfer Termination Methods 76 GPIB Status Conditions 77 GPIB Error Conditions 78 Serial Port Error Conditions 86 Wait Mask Values xiv...

Страница 13: ... and executing high level commands that you send to it over the Macintosh serial port Introduction to the IEEE 488 GPIB The IEEE 488 also known as the General Purpose Interface Bus or GPIB is a high speed parallel bus structure originally designed by Hewlett Packard It is generally used to connect and control programmable instruments but has gained popularity in other applications such as intercom...

Страница 14: ...elsius and in humidity ranging from 10 to 95 non condensing The GPIB MAC can be stored in temperatures ranging from 0 to 70 degrees Celsius Physical Specifications The GPIB MAC shown in the following figure is housed in a structural foam injection molded case The unit can be rack mounted or placed on a table Model GPIB MAC 2 SECTION ONE INTRODUCTION ...

Страница 15: ...r panel switches of the GPIB MAC More detailed configuration information is included in Section Two The Model GPIB MAC Front Panel The front panel of the GPIB MAC is shown in the following figure The six light emitting diodes LEDs show the current status of the GPIB MAC NATIONAL INSTRUMENTS GPIB MAC IEEE 488 MAC p ll l Front Panel of the GPIB MAC 3 SECTION ONE INTRODUCTION ...

Страница 16: ... GPIB MAC is currently addressed to Talk on the GPIB indicates that the GPIB MAC is currently addressed to Listen on the GPIB indicates that the GPIB signal line ATN is asserted low indicates that the GPIB signal line SRQ is asserted low The Model GPIB MAC Back Panel The back panel of the GPIB MAC is shown in the following figure The power connector 9 position configuration switch g pin D subminia...

Страница 17: ...November 1985 0 National Instruments Power GPIB IEEE 488 Connector Port g pin D subminiature Connector 9 position Configuration Switch Back Panel of the Model GPIB MAC 5 SECTION ONE INTRODUCTION ...

Страница 18: ...330 2 mm 13 0 inches Weight 5 25 pounds Electrical Specifications The GPIB MAC is designed to operate under the following electrical specifications Power 115 volts AC or 230 volts AC 50 60 Hz 20 VA Typical Current 09 amps AC Fuse Type 115 volts AC use l 4 amp Fast 230 volts AC use l 8 amp Fast 6 SECTION ONE INTRODUCTION ...

Страница 19: ...ible inspection or for reshipment If the equipment appears to be damaged do not attempt to operate it Contact National Instruments for instructions Installation There are four basic steps to installing the GPIB MAC 1 Verify voltage requirements 2 Configure GPIB MAC rear panel switches 3 Connect cables 4 Turn power switch to On Voltage Requirements The GPIB MAC is shipped with the internal voltage ...

Страница 20: ...itches labeled for factory use only 7 or g bit word length one or two stop bits odd even or no parity and baud rate 011 4800 100 9600 101 19 2K 110 38 4K 111 57 6K GPIB MAC DIP Switch Switches 1 and 2 Factorv Use Only Switch 1 and 2 are for factory use only and should always be positioned in the off position as shown below Factory Use Only D OFF l ON 8 SECTION TWO INSTALLATION AND CONFIGURATION ...

Страница 21: ...ch 3 Word Length Configure the GPIB MAC for a serial word length of 7 or 8 bits by setting switch 3 The off position indicates 7 bits the on position indicates 8 7 bit Word Length g bit Word Length 9 SECTION TWO INSTALLATION AND CONFIGURATION ...

Страница 22: ... 1985 Switch 4 StoD Bits Configure the GPIB MAC for a stop bit length of 1 or 2 bits by setting switch 4 The off position indicates 1 bit the on position indic s 2 1 Stop Bit 2 Stop Bits 10 SECTION TWO INSTALLATION AND CONFIGURATION ...

Страница 23: ... Configure the GPIB MAC for the correct parity according to the following figure Note that switch 5 indicates parity off Switch 6 indicates parity odd or even If switch 5 is set to off switch 6 is ignored Switch Settines Parity Type _ 1 2 3 415 6i7 8 9 Odd Parity Even Parity Pa y Inhibit Parity Inhibit b_______ 11 SECTION Two INSTALLATION AND CONFIGURATION ...

Страница 24: ...itches 7 8 and 9 Baud Rate Configure the GPIB MAC for the appropriate baud rate by setting switches 7 8 and 9 according to the following figures Switch Settings Baud Rate 300 1 1 2 0 0 2400 4800 12 SECTION TWO INSTALLATION AND CONFIGURATION ...

Страница 25: ...ber 1985 0 National Instruments B a u d 9600 19 2K 38 4K 57 6K If you need more information on how the switches of the GPIB MAC should be set refer to Appendix G 13 SECTION TWO INSTALLATION AND CONFIGURATION ...

Страница 26: ...nel If 115 VAC is required use the standard power cable supplied with the unit If 230 VAC is required use a cable that is compatible with both the GPIB MAC power receptacle and the 230 VAC plug configuration The GPIB cable should be connected to the 24 pin GPIB connector on the lower right of the rear panel The connectors can be piggy backed to add more GPIB devices to the bus Connect the serial c...

Страница 27: ...BEADY LED comes on If it does not verify your switch settings and the power connections If the BEADY LED still fails to come on contact National Instruments Note The rear panel switches are read by the fiiware only when the unit is powered on After changing switch settings turn the power switch off and back on for the change to take effect Also the GPIB address of the GPIB MAC at power on is 0 wit...

Страница 28: ...sts of a function name one or more arguments optional followed by a carriage return CR a linefeed LF or a carriage return followed by a linefeed CR LF You may enter programming messages in any combination of uppercase and lowercase letters Example of 3 Proaramming Message The following line of BASIC code PRINT l clr 34 contains the function name clr and the arguments 3 and 4 This programming messa...

Страница 29: ... processes a programming message on a line by line basis The GPIB MAC buffers the entire message interprets the function name and arguments then executes the message The data portions of the wrt and cmd functions are not processed on a line by line basis The data immediately following a wrt and a cmd are sent directly to the GPIB Function Names The function names have been selected to indicate eac...

Страница 30: ...breviations for Arguments The function descriptions in Section Four use abbreviations for some arguments They are as follows addr a GPIB address alist one or more addrs boo1 a boolean value 1 true on or enable 0 false off or disable GPIB Address Each device on the GPIB has a GPIB address The GPIB MAC s address is 0 at power on and may be changed using the caddr function Refer to the manuals of you...

Страница 31: ...e it with a backslash 0 To specify a hexadecimal integer precede it with a backslash x ox or backslash X OX Each of the following numeric strings represents the decimal integer value 112 112 160 x70 The GPIB address argument described previously under GPIB Address consisted of one or two numeric strings Status Information The function descriptions in Section Four explain that the GPIB MAC records ...

Страница 32: ...PIB Talkers and Listeners may identify the last byte of data messages END and EOS The two methods permit a Talker to send data messages of any length without the Listener s knowing in advance the number of bytes in the transmission END message the Talker asserts the EOI End or Identify signal while the last data byte is being transmitted The Listener stops reading when it detects a data byte accom...

Страница 33: ...ho bytes to serial port ignore serial port errors send XON XOFF recognize XON XOFF Power on Value Function no echo Yes spign no xon no xon GPIB CHARACTERISTICS Characteristic power on Value primary secondary address pad O sad none end of string modes none send END on writes ist bit setting yo GPIB MAC is System Controller yes I O timeout 10 set serial poll timeout l set Function caddr eos cot ist ...

Страница 34: ...data data BUS Function CLR address list LOC address list TRG address list MANAGEMENT FUNCTIONS Pupose Cl sgzed device s Trigger selected device s GPIB INITIALIZATION FUNCTIONS Function CADDR address EOS modes eoschar EOT on off ONL on off RSC on off TM0 values Puipose Change the GPIB address of the GPIB MAC Change disable GPIB EOS termination mode Enable disable END message on GPIBwrites Place the...

Страница 35: ...ode PCT address SIC time SRE on off PARALLEL POLL Function IST on off PPC values PPU address list RPP Pur_Dose Become active controller Send IEEE 488 commands Go from Active Controller to Standby Pass Control Send interface clear Set clear remote enable FUNCTIONS Purpos 2 Set or clear individual status bit for use in GPlB MAC response to Parallel Polls Parallel Poll Configure Parallel Poll Unconfi...

Страница 36: ...ONS Function Purpwl IDMAC STAT modes WAIT mask Identify system Return GPIB MAC status Wait for selected event List of Functions in Alphabetical Order The following is an alphabetical list of all functions GPIB MAC FUNCTIONS Function CAC mode CADDR address CLR address list CMD count commands ECHO on off m Become active controller Change GPIB address of the GPIB MAC Clear specified device s Send GPI...

Страница 37: ...Active Controller to Standby Identify system Set or clear individual status bit for use in GPIB MAC response to Parallel Polls Go to Local Place the GPlB MAC online offline Pass Control Parallel Poll Configure Parallel Poll Unconfigure Read data Request conduct a Parallel Poll Request or release System Control Request conduct a serial poll Request service set or change the serial poll status byte ...

Страница 38: ...d IF or a carriage return followed by a linefeed CR LF The terminator is denoted by CR in the syntax portions of the function descriptions In the program ming examples the BASIC PRINT statement automatically sends a carriage return at the end of the string so a carriage return is not placed there explicitly 4 To send more than one programming message per PRINT statement embed a CR denoted by CIIR ...

Страница 39: ... name to distinguish it from other functions Those characters are shown in boldface in the syntax portion of each function description 7 I O and bus management functions meet most of your needs In the descriptions that follow these frequently used functions are marked with an asterisk 28 SECTION FOUR FUNCTIONS ...

Страница 40: ... GPIB MAC takes control immediately that is it takes control asynchronously If the argument boo1 is 0 the GPIB MAC takes control after any handshake that is in progress completes that is it takes control synchronously If you call cat without an argument the GPIB MAC returns to you the current controller status which is 0 if the GPIB MAC is m the Active Controller and1 if the GPIB MAC h the Active ...

Страница 41: ...0 National Instruments Examples 1 PRINT l cac 1 Take control immediately 2 PRINT 1 cac 0 Take control synchronously 3 PRINT l CAC Are we the active controller response lcCRxLF yes we re CAC 30 SECTION FOUR FUNCTIONS ...

Страница 42: ...address are significant These bits may be in the range from 0 through 30 for both the primary and the secondary address Therefore the binary value 01100010 decimal 98 is interpreted as decimal 2 The following examples all specify a primary address of 0 and a secondary address of 2 The listen address is 32 the talk address is 64 and the secondary address is 2 or 98 which are equivalent 0 2 or 0 98 ...

Страница 43: ...ng disabled Examples 1 PRINT l caddr 0 22 Give GPIB MAC a primary address of 0 and a secondary address of 22 2 PRINT l CADDR 1 Change GPIB MAC primary address to 1 and disable secondary addressing 3 PRINT l CADDR Return current GPIB MAC address response lcCRxLF 32 SECTION FOUR FUNCTIONS ...

Страница 44: ...ice address consists of a primary address and an optional secondary address The secondary address is separated from the primary address by a plus sign Only the lower five bits of each address are significant These bits may be in the range from 0 through 30 for both the primary and the secondary address Therefore the binary value 01100010 decimal 98 is interpreted as decimal 2 The following example...

Страница 45: ...ith csc the GPIB MAC sends Interface Clear IX to make itself CIC It also asserts Remote Enable Refer to Appendix D for more information on clearing devices Refer to Appendix B for more error information Examples 1 PRINT l clr 14 30 16 12 18 3 26 6 Selectively clear 5 devices 2 PRINT l CLR Issue Device Clear to all devices frequently used function 34 SECTION FOUR FUNCTIONS ...

Страница 46: ...e messages to send which is a number between 1 and 255 The number of command bytes must not include the carriage return or linefeed that you include to indicate the end of the programming message The argument commands is a list of GPIB commands These commands are represented by their ASCII character equivalents For example the GPIB Untalk UNT command is the ASCII character underscore C Refer to Ex...

Страница 47: ...uccessfully transfers all commands the GPIB MAC detects an error GPIB MAC is not CIC the I O time limit is exceeded the Take Control TCT command is in your command string and is sent to the GPIB the Interface Clear IX message is received from System Controller not the GPIB MAC After cmd terminates the GPIB MAC records the number of command bytes it actually sent If an event in the above list occur...

Страница 48: ...ndix A to convert hex values to ASCII characters Examples 1 PRINT l cMD PRINT l PRINT 1 WI W PRINT 1 I ABCDE Program device at address 11 to listen and GPIB MAC at address 0 to talk Device listen address is 43 or ASCII and GPIB MAC talk address is 64 or ASCII Write the string ABCDE to device at address 11 2 PRINT l cmd tCHR 13 W CHR 9 Pass control to device 23 CHR 9 TCT command 37 SECTION FOUR FUN...

Страница 49: ...he serial port If the argument boo1 is 0 characters are not echoed If the argument boo1 is 1 and echoing was previously disabled characters will not be echoed until this command has been completely processed i e the m programming message will be echoed If you call echo without an argument the GPIB MAC returns the current setting Note The following examples show commands as you would enter them at ...

Страница 50: ...to be recognized as a string terminator Remarks The arguments R X B and D specify GPIB termin ation methods They enable or disable the corresponding eos mode If a particular letter is specified the corres ponding eos mode is enabled If it is not specified the corresponding eos mode is disabled eoschar is a numeric string which represents a single ASCII character For example 10 represents the ASCII...

Страница 51: ...s of the EOS character If Methods X and B are chosen a full g bit comparison is used Note that defining an EOS byte for the GPIB MAC does not cause the GPIB MAC to insert that byte into the data string when performing GPIB writes To send the EOS byte you must include it in the data string that you send following the wrt programming message By default no eos modes are enabled If you call eos with B...

Страница 52: ...fer Input string that indicates number of bytes actually read from GPIB PRINT COUNT bytes were read from GPKB Print number of bytes that were read from the GPIB 2 PRINT l EOS X 13 PRINT l wrt lO 5 Tell GPIB MAC on wrt send EOI with CR on rd do not terminate when CR is detected compare 7 bits GPIB MAC sends EOI with CR CHR 13 to tell listeners that this is the last byte of data PRINT 1 012345678 CH...

Страница 53: ... END message with the last byte of each wrt If the argument boo1 is 0 END is not sent The power on default is 1 If you call eot without an argument the GPIB MAC returns to you a 1 to indicate END termination is currently enabled or a 0 to indicate END termination is currently disabled The assignment made by eot remains in effect until you call eot again call onl or you turn off the GPIB MAC The GP...

Страница 54: ... byte PRINT l WRT 3 Write data to device at address 3 PRINT 1 ABCDE The EOI line is automatically asserted when the last byte the letter E is sent to tell the Listeners it is the last byte of data 3 PRINT l eot What is the current EOT setting response lcCRxLF END termination is currently enabled 43 SECTION FOUR FUNCTIONS ...

Страница 55: ...onously without possibly corrupting the transfer Remarks If the argument boo1 is 1 shadow handshaking is enabled If the argument boo1 is 0 shadow handshaking is not performed If you call gts without an argument the GPIB MAC returns to you the current controller status CSB O if the GPIB MAC is in Standby without shadow handshaking CSB l if the GPIB MAC is in Standby with shadow handshaking CAC if t...

Страница 56: ... cmd or rpp Before performing a gts with a shadow handshake you should call eos to establish the proper end of string character or to disable the EOS detection if the end of string character used by the talker is not known If you call gts with an argument and the GPIB MAC is not CIC the GPIB MAC records the ECIC error Refer also to cat Examples 1 PRINT l gts 0 GTS without shadow handshaking 2 PRIN...

Страница 57: ...nstalled in your GPIB MAC Remarks The identification is returned in three strings The first two strings identify the company product model the software revision level and a copyright notice The third string identifies the number of bytes of RAM in the GPIB MAC Example PRINT 1 idhIAC Get system identification response GPIB MAC Rev A OcCRxLF c 1985 National InstrumentscCR cLF 2K bytes RAMcCR cLF 46 ...

Страница 58: ...the argument boo1 is 1 the GPIB MAC s individual status bit is set to 1 If the argument boo1 is 0 the GPIB MAC s individual status bit is cleared The power on default is 0 If you call ist without an argument the GPIB MAC returns the value of its individual status bit Refer also to ppc and Appendix F Examples 1 PRINT l ist 1 Set ist to 1 2 PRINT l IST 0 Clear ist to 0 3 PRINT l ist What is ist set ...

Страница 59: ...evices you wish to return to local mode A device address consists of a primary address and an optional secondary address The secondary address is separated from the primary address by a plus sign Only the lower five bits of each address are significant These bits may be in the range from 0 through 30 for both the primary and the secondary address Therefore the binary value 01100010 decimal 98 is i...

Страница 60: ... send IPC to make yourself CIC before making this call Otherwise the ECIC error will be posted If you call loc without alist and the GPIB MAC is System Controller the GPIB MAC returns all devices to local mode by unasserting REN and asserting it again If you call lot without alist and the GPIB MAC is not System Controller the GPIB MAC records the ESAC error Refer to Appendix B for more error infor...

Страница 61: ...in the Idle Controller state and configures itself to be the System Controller If you call on1 without an argument the GPIB MAC returns the current status of the GPIB MAC which is 0 if the GPIB MAC is offline and 1 if the GPIB MAC is online Placing the GPIB MAC offline may be thought of as disconnecting its GPlB cable from the other GPIB devices Placing the GPIB MAC online allows the GPIB MAC to c...

Страница 62: ...National Instruments Examples 1 PRINT l onl 1 Put the GPIB MAC online and restore its power on settings 2 PRINT l ONL 0 Put the GPIB MAC offline to prevent it from communicating with the GPIB 51 SECTION FOUR FUNCTIONS ...

Страница 63: ...e in the range from 0 through 30 for both the primary and the secondary address Therefore the binary value 01100010 decimal 98 is interpreted as decimal 2 The following examples all specify a primary address of 0 and a secondary address of 2 The listen address is 32 the talk address is 64 and the secondary address is 2 or 98 which are equivalent 0 2 or 0 98 or 32 98 or O x62 pet passes CIC authori...

Страница 64: ...November 1985 0 National Instruments Example PRINT l pct 7 18 Pass control to device with primary address 7 and secondary address 18 53 SECTIONFOUR FUNCTIONS ...

Страница 65: ...cant These bits may be in the range from 0 through 30 for both the primary and the secondary address Therefore the binary value 01100010 decimal 98 is interpreted as decimal 2 The following examples all specify a primary address of 0 and a secondary address of 2 The listen address is 32 the talk address is 64 and the secondary address is 2 or 98 which are equivalent 0 2 or 0 98 or 32 98 or O x62 T...

Страница 66: ...se the ECIC error will be posted The GPIB MAC takes the arguments ppr and s and constructs the appropriate parallel poll enable PPE message for each addr specified When addr is the address of the GPIB MAC the GPIB MAC programs itself to respond to a parallel poll by setting its local poll enable lpe message to the value specified Refer also to ist ppu rpp and to Appendix F on parallel polling Exam...

Страница 67: ...ess is separated from the primary address by a plus sign Only the lower five bits of each address are significant These bits may be in the range from 0 through 30 for both the primary and the secondary address Therefore the binary value 01100010 decimal 98 is interpreted as decimal 2 The following examples all specify a primary address of 0 and a secondary address of 2 The listen address is 32 the...

Страница 68: ...ontrol to some other GPIB device control must be passed back to you or you must send IFC to make yourself CIC before making this call Otherwise the ECIC error will be posted If the address of the GPIB MAC is included in alist the GPIB MAC disables itself from responding to parallel polls Refer also to ist ppc rpp and to Appendix F on parallel polls Examples 1 PRINT l ppu 14 Send the PPU command to...

Страница 69: ...separated from the primary address by a plus sign Only the lower five bits of each address are significant These bits may be in the range from 0 through 30 for both the primary and the secondary address Therefore the binary value 01100010 decimal 98 is interpreted as decimal 2 The following examples all specify a primary address of 0 and a secondary address of 2 The listen address is 32 the talk a...

Страница 70: ...F A null byte is decimal 0 You should always read back count bytes of data from the serial port then look at the remaining bytes to determine how many of the count bytes were read from the GPIB Refer to the example at the end of this description The GPIB MAC aborts the GPIB read and records the EABO error if at any time during the GPIB read the time limit set for I O functions expires This limit i...

Страница 71: ... the ECIC error will be posted If the GPIB MAC is not CIC and you do not specify the talker address the GPIB MAC assumes it will be addressed by the Controller then proceeds If you call rd without an argument the GPIB MAC records the EARG error Refer also to tmo Example PRINT l rd lO 3 RESP INPUT lO l Read up to 10 bytes from the GPIB device at address 3 Input 10 bytes from serial port buffer LINE...

Страница 72: ...d responses within that time It remains Active Controller afterward The GPIB MAC returns the Parallel Poll Response PPR following the poll in the form of a numeric string representing the decimal value of the response If this is the first function you call that requires GPIB controller capability and you have not disabled System Controller capability with rsc the GPIB MAC sends Interface Clear IFC...

Страница 73: ...2 devices for parallel polls and poll them response ScCRxLF both devices responded positively LINE INPUT l RESP PPR VAL RESP Get parallel poll response from serial port buffer and assign it to integer variable PPR PRINT 1 ppu configure all devices from parallel polls 62 SECTION FOUR FUNCTIONS ...

Страница 74: ...Controller As System Controller the GPIB MAC can send the Inter face Clear IX and Remote Enable EN messages to GPIB devices If some other Controller asserts Interface Clear the GPIB MAC cannot respond unless it is configured as not System Controller In most applications the GPIB MAC will be System Controller In some applications the GPIB MAC will never be System Controller In either case rsc is us...

Страница 75: ...mples 1 PRINT l rsc 1 Enable GPIB MAC to be system controller 2 PRINT l rsc 0 Disable system control 3 PRINT l rsc What is the current system controller status response OcCR cLF GPIB MAC is not the System Controller 64 SECTION FOUR FUNCTIONS ...

Страница 76: ... by a plus sign Only the lower five bits of each address are significant These bits may be in the range from 0 through 30 for both the primary and the secondary address Therefore the binary value 01100010 decimal 98 is interpreted as decimal 2 The following examples all specify a primary address of 0 and a secondary address of 2 The listen address is 32 the talk address is 64 and the secondary add...

Страница 77: ...h response corresponds directly to an address you specify therefore there are exactly as many lines of responses including 1 as the number of addresses you specify If you call rsp and the GPIB MAC is not CIC it attempts to become CIC If it cannot become CIC it records the ECIC error Refer to Appendix B for more information If this is the first function you caIl that requires GPIB controller capabi...

Страница 78: ...dwithin 30cCR cLF the timeout period lcCR LF DBlSPR 2 Read 3 responses from serial port buffer FOR I 0 to 2 LINE INPUT l RESP Store each serial poll response in SPR I VAL RESP the array SPR IF SPR I 1 THEN GOSUB 1000 1000 is an error NEXT1 routine REM Code will now interpret serial poll responses 67 SECTION FOUR FUNCTIONS ...

Страница 79: ...ifying the decimal value of the new GPIB MAC serial poll response byte The serial poll response byte is the status byte the GPIB MAC provides when serially polled by another device that is CIC If bit 6 hex 40 RQS bit is also set the GPIB MAC additionally requests service by asserting the SRQ line If you call rsv without an argument the GPIB MAC returns a numeric string containing the decimal value...

Страница 80: ...omma If you call sic without an argument IFC is sent for 500 microseconds The action of asserting IFC for at least 100 microseconds initializes the GPIB and makes the interface board become CIC When needed sic is generally used at the beginning of a program to make the GPIB MAC CIC and is used when a bus fault condition is suspected The IFC signal resets only the GPIB interface functions of bus de...

Страница 81: ...Controller capability with the rsc function It records the EARG error if you specify a time outside the range BOO1 to 3600 Refer also to clr and to Appendix D Examples 1 PRINT l sic Send interface clear for 500 microseconds 2 PRINT l SIC Ol Send interface clear for 10 milliseconds 70 SECTION FOUR FUNCTIONS ...

Страница 82: ...te programming messages that con tain serial port errors A list of serial port errors are listed in Appendix B Also if a serial port error occurs with any byte contained in a cmd or wrt data string the GPIB MAC discards that data byte and all remaining bytes in the string The serial port errors include parity overrun framing and overflow errors If the argument boo1 is 1 the GPIB MAC executes all p...

Страница 83: ...Examples 1 PRINT l spign 0 Do not execute programming messages or process data that contain serial port errors 2 PFUNT l spign 1 Execute all programmh g messages and send all data even if serial port errors occur 72 SECTION FOUR FUNCTIONS ...

Страница 84: ...ts the Remote Enable EN signal If the argument boo1 is 0 the GPIB MAC unasserts REN Many GPIB devices have a remote program mode and a local program mode It is usually necessary to place devices in remote mode before programming them from the GPIB A device enters the remote mode when the REN line is asserted and the device receives its listen address Use cmd to send a device its listen address aft...

Страница 85: ...November 1985 0 National Instruments Examples 1 PRINT l SRE 1 Set REN 2 PRINT l sre 0 Unassert REN 74 SECTION FOUR FUNCTIONS ...

Страница 86: ...ending on the mode or combination of modes you chose n indicates that the status information will be returned as numeric strings s indicates that the status information will be returned in symbolic format i e as mnemonic strings c specifies that the status will be returned after each programming message eliminating the need to call stat after each programming message Normally you use s only when y...

Страница 87: ...hen the GPIB MAC detects either a GPIB error or a serial port error Consequently when status is negative an error condition exists and when status is positive no error condition exists gpib error represents a single GPIB error condition present serial error represents a single serial error condition present count is the number of bytes transferred over the GPIB by the last rd wrt or cmd function G...

Страница 88: ... LACS Listener active DTAS Device trigger state DCAS Device clear state GPIB ERROR CONDITIONS Symbolic Value s Description NGER ECIC ENOL EADR EARG ESAC EABO E D No GPIB error condition to report Command requires GPIB MAC to be CIC Write detected no listeners GPIB MAC not addressed correctly Invalid argument or arguments Command requires GPIB MACtobeSC I O operation aborted Reserved Unrecognized c...

Страница 89: ...amming message For example if you call wrt and then stat s any errors returned to you correspond to errors in the wrt programming message not stat However if status is returned in continuous mode the status information corresponds to the current programming message For example suppose you call stat c s to set up continuous status reporting After reading the status information returned for the stat...

Страница 90: ...n the overall performance of your program If speed is a primary concern disable continuous status reporting Examples 1 10 PRINT l stat n Get GPIB MAC status 20 REM GPIB MAC responds with 30 REM 340 CR LF OcCR LF O CR LF Oc LF 40 REM Now read status into variables 50 STATUS VAL LINE INPUT l STATUS 60 LINE INPUT 1 GPIBERR 70 LINE INPUT l SPERR 80 LINE INPUT l COUNT 90 REM Go to error routine at 500 ...

Страница 91: ...rates what appears on the screen when you are programming the GPIB MAC from a terminal Programming messages you enter are in normal type GPIB MAC responses are in bold The statements in parentheses are comments stat c s n enable continuous status reporting 344 8 3 CMPL REM ATN TACS status returned NGER NSER 3 wrt 10 ABCDE Write the string ABCDE 344 device 10 0 Status returned s CMPL REM ATN TACS N...

Страница 92: ...10 seconds for timeio and l 10 of a second for timesp timeio and timesp may be any decimal number between OOOOl and 3600 which corresponds to time limits between 10 microseconds and 1 hour lO l specifies a time of 10 seconds for I O operations and l l0 of a second for serial poll response timeio and timesp may also be 0 which disables either timeout accordingly Neither timeio nor timesp may contai...

Страница 93: ... without an argument the GPIB MAC returns a numeric string representing the cuxmnt timeout settings It records the EARG error if you specify a time value outside the range OOOOl to 3600 The assignment made by this function remains in effect until you call tmo again call onl or turn off the GPIB MAC Examples 1 PRINT l tmo 30 Set timeout for If0 operations to 30 seconds leave serial poll timeout unc...

Страница 94: ...plus sign Only the lower five bits of each address are significant These bits may be in the range from 0 through 30 for both the primary and the secondary address Therefore the binary value 01100010 decimal 98 is interpreted as decimal 2 The following examples all specify a primary address of 0 and a secondary address of 2 The listen address is 32 the talk address is 64 and the secondary address i...

Страница 95: ...some other GPIB device control must be passed back to you or you must send IFC to make yourself CIC before making this call Otherwise the ECIC error will be posted Example PRINT l trg 2 10 4 5 7 Trigger 3 devices frequently used function 84 SECTION FOUR FUNCTIONS ...

Страница 96: ...GPIB activity When any event corresponding to the bits set in mask occurs the GPIB MAC returns status information indicating its current status If continuous status reporting has been enabled status will be reported in the format requested If continuous status has not been enabled status will be returned in numeric format You could use wait for example if you wish to wait until a device requests s...

Страница 97: ...served Reserved Reserved Lockout state Remote state Controller In Charge Attention asserted Talker active Listener active Device trigger state Device clear state If mask 0 the function completes immediately If the TIM0 bit is 0 or the timeio time limit is set to 0 with tmo timeouts for this function are disabled You should disable timeouts only when you are certain the selected event will occur ot...

Страница 98: ...an error routine at line 1000 IF STATUS AND HlOOO 0 THEN GOT0 200 If SRQI bit set go to routine to conduct a serial poll 2 PRINT l wait 4 Wait indefinitely to become LACS STATUS VAL LINE INPUT l STATUS Get status info GPIBERR VAL LINE INPUT l GPIBERR SPERR VAL LINE INPUT l SPERR COUNT VAL LINE INPUT l COUNT PRINT l rd lo Now that GPIB MAC is addressed to listen read 10 bytes from the GPIB RESP INP...

Страница 99: ... a list of addrs separated by commas or spaces addrs are addresses that specify the GPIB addresses of the Listener or Listeners if more than one address is given A device address consists of a primary address and an optional secondary address The secondary address is separated from the primary address by a plus sign Only the lower five bits of each address are significant These bits may be in the ...

Страница 100: ...ing this call Otherwise the ECIC error will be posted If you do not give an alist and the GPIB MAC is not CIC it assumes it will be addressed by the controller If you do not give an alist and the GPIB MAC is CIC it addresses itself as talker and assumes the listeners are already addressed The first part of this programming message up to CR is buffered meaning the GPIB MAC will not act upon it unti...

Страница 101: ...o to tmo for timeout information to Appendix B for more error information and to spign for serial port error handling information Examples 1 PRINT l wrt 50 9 97 Write 50 bytes to device at FORI 1 TO50 I I l CI AO primary address 9 and secon dary address 97 PRINT l CHR 13 Send carriage return 2 PRINT l wlt 2 PRINT l ABCDE Write the data bytes ABCDE at device at address 2 frequently used function 90...

Страница 102: ...haracter decimal 17 or c q it begins sending data again If you want to send a data string that may contain a ctrl s or ctrl q you must disable booltx The argument boolrx specifies whether to enable the XON XOPP protocol when receiving data over the serial port If the argument boolrx is a 1 and the GPIB MAC is receiving data over the serial port it sends XOFJ over the serial port if its serial rece...

Страница 103: ...tings l protocol enabled O protocol disabled Examples 1 PRINT l XON 1 l Enable GPIB MAC XON XOPP protocol for TX and RX 2 PRINT l XON 0 l Disable protocol on TX enable protocol on RX 3 PRINT l XON Return current settings response O lcCR cLF transmit protocol disabled receive protocol enabled 4 PRINT l XON O Disable protocal on RX keep current setting on TX 92 SECTIONFOUR FUNCTIONS ...

Страница 104: ...vember 1985 0 National Instruments Appendix A Multiline Interface Messages The following tables are multiline interface messages Sent and Received with ATN TRUE 93 APPENDIX A MULTILINE INTERFACE MESSAGES ...

Страница 105: ... 16 026 22 SYN 17 027 23 ETB 18 030 24 CAN 19 031 25 EM 1A 032 26 SUB 1B 033 27 ESC 1C 034 28 FS 1D 035 29 GS 1E 036 30 RS 1F 037 31 US GTL SDC PPC GET TCT DCL PPU SPE SPD 20 040 32 SP 21 041 33 22 042 34 23 043 35 24 044 36 25 045 37 8 26 046 38 27 047 39 28 050 40 29 051 41 2A 052 42 2B 053 43 2c 054 44 2D 055 45 2E 056 46 2F 057 47 30 060 48 0 31 061 49 1 32 062 50 2 33 063 51 3 34 064 52 4 35 ...

Страница 106: ...MTA 6C 154 MTA 6D 155 MTA 6E 156 MTA 6F 157 MTA 70 160 MTA 71 161 MTA 72 162 MT A 73 163 MTA 74 164 MTA 75 165 MTA 76 166 MTA 77 167 MTA MTA MTA MTA MTA MTA MTA 78 170 79 171 7A 172 7B 173 7c 174 7D 175 7E 176 7F 177 96 97 a b 100 d 101 e 102 f 103 g 104 h 105 i 106 j 107 k 108 1 109 m 110 n 111 0 112 p 113 q 114 r 115 s 116 t 117 u 118 v 119 w 120 x 121 y 122 z 123 124 I 125 126 127 DEL MS A PPE ...

Страница 107: ...ing this bit you may check for an error condition after each call An error made early in your application program may not become apparent until a later instruction At that time the error can be more difficult to locate 16384 The TIM0 bit specifies whether a timeout has occurred The TIM0 bit is set in the status word following a call to wait if the TIM0 bit of the wait mask parameter is also set an...

Страница 108: ...ifying the status word from other responses 128 The LOK bit specifies whether the GPIB MAC is in a lockout state The LOK bit is set whenever the GPIB MAC detects the Local Lockout LLO message has been sent either by the GPIB MAC or by another Controller The LOK bit is cleared when the Remote Enable EN GPIB line becomes unasserted either by the GPIB MAC or by another Controller 64 The REM bit speci...

Страница 109: ...The TACS bit is set whenever the GPIB MAC detects that its talk address and secondary address if enabled has been sent either by the GPIB MAC itself or by another Controller The TACS bit is cleared whenever the GPIB MAC detects the Untalk UNT command a talk address other than its own its own listen address or Interface Clear IX LACS 4 The LACS bit specifies whether the GPIB MAC has been addressed ...

Страница 110: ...her Controller or whenever the GPIB MAC as a Listener detects the Selected Device Clear SDC command has been sent by itself or by another Controller The DCAS bit is cleared in status at the start of any subsequent programming message In addition to the above the following situations also affect the bits in status A calI to the on1 function clears the following bits END LGK REM CIC TACS LACS DTAS D...

Страница 111: ...e calls If it is not you may call wait 32 to wait to become CIC and to delay further processing until control is passed to the GPIB MAC 2 The most common cause of this error is that the GPIB MAC attempted to write to the GPIB when no listeners were addressed The remedy is to be sure that the proper listen address is in the alist argument string to use cmd to properly address the listeners or to be...

Страница 112: ...llel poll configurations If your programming message contains more than one argument and you get this error the GPIB MAC discards all arguments and does not perform the function This also may be caused by a transmission error which corrupts the argument portion of the programming message or which corrupts the CR or LF that terminates the programming message Use stat and check serial error to deter...

Страница 113: ...lted in the function name being corrupted Check your function name spelling and check serial error to see if a serial port error has been posted Serial Port Error Codes The following paragraphs describe the serial port errors in detail When a serial port error occurs as the GPIB MAC receives a programming message the GPIB MAC posts the error and discards the message If a serial port error occurs i...

Страница 114: ...your Macintosh are using the same serial port settings EOPL 3 The GPIB MAC records this error when the GPIB MAC s internal serial port buffer overflows This should only occur if XON XOPP is disabled EPRM4 The GPIB MAC records this error when a character is received whose stop bits are not in the expected place This can happen when the number of bits per character setting of the GPIB MAC does not m...

Страница 115: ...anel of the GPIB MAC Disconnect the power cord from the power source and from the rear panel of the GPIB MAC Remove the cover from the GPIB MAC by fast removing the two screws on both sides of the housing Lift off the cover Change the setting of the red power selector switch so that it reads 230V The following figure shows the location of the power selector switch GPIB MAC with Cover Removed 105 A...

Страница 116: ...uminum side plates are in the proper place Replace the screws you removed in Step 1 6 Remove the fuse assembly Replace the l 4 ampere fuse supplied with the GPIB MAC with a l 8 ampere fuse Re insert the fuse assembly 106 APPENDIX C CHANGING FROM 115 Volts AC TO 230 Volts AC ...

Страница 117: ...gh the interface system There are two types of messages Device dependent messages often cakd data or data messages contain device specific information such as programming instructions measurement results machine status and data files Interface messages manage the bus itself They are usually called commands or command messages Interface messages perform such functions as initializing the bus addres...

Страница 118: ...ty device wants to make a call send a data message it connects the caller Talker to the receiver Listener The Controller usually addresses a Talker and a Listener before the Talker can send its message to the Listener After the message is transmitted the Controller usually unaddresses both devices Some bus configurations do not require a Controller For example one device may only be a Talker calle...

Страница 119: ... 8 ground return or shield drain lines The 16 signal lines are divided into three groups 8 datalines 3 handshake lines 5 interface management lines The following figure shows the arrangement of these signals on the GPIB cable connector DIO8 REN GPIB Cable Connector 109 APPENDIX D OPERATION OF THE GPIB ...

Страница 120: ...dicates when a device is ready or not ready to receive a message byte The line is driven by all devices when receiving commands and by Listeners when receiving data messages NDAC not data accepted NDAC indicates when a device has or has not accepted a message byte The line is driven by all devices when receiving commands and by Listeners when receiving data messages DAV data valid DAV tells when t...

Страница 121: ... local program mode SRQ service request Any device can drive the SRQ line to asynchronously request service from the Active Controller with the SRQ line EOI end or identify The EOI line has two purposes The Talker uses it to mark the end of a message string The Active Controller uses it to tell devices to identify their responses in a parallel poll Physical and Electrical Characteristics Devices a...

Страница 122: ...November 1985 0 National Instruments El Macintosh w i t h GPIB MAC Linear Configuration of GPIB Devices 112 APPENDIX D OPERATION OF THE GPIB ...

Страница 123: ...November 1985 0 National Instruments Device B I I Device C Star Configuration of GPIB Devices 113 APPENDIX D OPERATION OF THE GPIB ...

Страница 124: ...n Restrictions To achieve the high data transfer rate that the GPIB is designed for the physical distance between devices and the number of devices on the bus is limited The following restrictions are typical A maximum separation of four meters between any two devices and an average separation of two meters over the entire bus A maximum total cable length of 20 meters No more than 15 devices conne...

Страница 125: ...to a variable Use INPUT to read a data string from your GPIB device INPUT requires that you know the exact number of characters you wish to read from the serial port When reading status information from the GPIB MAC this is not always possible since the responses may vary in length from one call to the next But when reading a data string from your GPIB device you requested a certain number of byte...

Страница 126: ...lo to the GPIB MAC to serial poll device 10 Then I used LINE INPUT to read the response byte and got nothing but a carriage return and linefeed as a response Am I doing something wrong Answer No To conduct a serial poll the GPIB MAC must be Controller In Charge or it must be able to become Controller In Charge If the GPIB MAC cannot become Controller In Charge no serial poll is conducted and there...

Страница 127: ... listen address and a parallel poll enable PPE message There are 16 possible PPE messages hex 60 hex 6F The bits in the PPE message have the following meaning 1 U 1 S 1 DIOlines I I I l 8 0 11 I X XI xxx U S DIO when 0 hex 6X parallel poll is enabled when 1 hex 7X parallel poll is disabled when the device s ist individual status bit matches the S bit the device will assert the appropriate data lin...

Страница 128: ...ess 5 to respond on DIO line 3 when the ist bit is 1 the programming message would be ppc 5 3 1 The GPIB MAC takes the arguments 3 l and constructs the following parallel poll enable byte 1 U 1 S 1 DIOlines I I I 0 11 1 0 1 01i80 The value of this byte is hex 6A where U 0 enable S 1 thus when ist 1 the device will assert DIO line3 which corresponds to 010 in bits O 2 The ppc function sends the dev...

Страница 129: ...s on that line Disabling Parallel Poll Response The active controller may disable a specific device from responding to a parallel poll by calling ppu with the device address as a parameter ppu sends the device the Parallel Poll Disable command hex 70 binary 01 1 1 0000 which sets U to 1 to disable the device from responding to a parallel poll To unconfigure all devices the controller may call ppu ...

Страница 130: ...l respond positively on DIO line 1 when busy In this case the ppr s argument for each of them is 0 l Thus the configuration byte for each of them is 01101000 hex 68 When a parallel poll is conducted the controller can immediately find out if all line printers are free because the response in this situation will be 0 If any line printer is busy bit 0 of the parallel poll response will be 1 corres p...

Страница 131: ...aud rate 9600 parity none data bits 8 stop bits 2 If these defaults meet your needs set the switches on the GPIB MAC as follows You may want to change the default characteristics of the serial port on the Macintosh For instance you may want to run at a higher baud rate up to 57 6K baud To change the default characteristics to 57 6K baud no parity 8 data bits and 2 stop bits from within Microsoft B...

Страница 132: ...t the switches on the GPIB MAC as follows 1 2 3 4 5 6 7 8 9 1 Remember whatever serial port characteristics you decide to use you must set up both your Macintosh and your GPIB MAC to the exact same characteristics 122 APPENDIX G SETTING SWITCHES ...

Страница 133: ...initialization functions if you need to change default serial port settings Send GPIB initialization functions if you need to change default GPIB settings Communicate with the device using the rd and wrt functions and check status if you requested it After you initialize the GPIB MAC the rd and wrt functions may be the only functions you will need Using an HP 7475A Plotter with a Macintosh This ex...

Страница 134: ... BASIC statement at the beginning of your program to open and configure the serial port COMl and name it device l OPEN COM1 9600 n 8 1 as l Note that you will now use PRINT l to redirect strings to the serial port Now send the stat function if you want status information returned after every programming message To do this include the following code in your program PRINT 1 stat c n After you send t...

Страница 135: ...programming messages and reading back status after each Here is the heart of the program After each wrt string call the subroutine status which will check for errors The plotter s GPIB address is 5 PRINT l wrt 5 PRINT l in spl pal000 3000 ci500 GOSUB status status STAT VAL LINE INPUT l status LINE INPUT l gpiberr LINE INPUT 1 sperr LINE INPUT 1 cnt PRINT status gpiberr sperr cnt if stat 0 GOSUB er...

Страница 136: ...ments status STAT VAL LlNE INPUT l status LINE INPUT 1 gpiberr LINE INPUT 1 sperr LINE INPUT 1 cnt PFUNT stat gpiben sperr cnt if stat 0 GOSUB error error REM Place your code to handle errors here STOP 126 APPENDIX H SAh4PLE PROGRAM ...

Страница 137: ...ata to the GPIB MAC The program was compiled with Manx Aztec C 68K 106 F l The data file is read into memory once then sent to the serial driver in a loop Programming languages such as MacBasic and MacPascal have too much overhead to send data faster than 19200 t baud include quickdraw h include pb h File h Device managers include stdio h Standard I O include serial h include memory h include even...

Страница 138: ...pen modem port rc d n rc set baud stop databits setupport refAIn refAOut make buffer too big for input to overrun l fort inLen 1 14 inLen hh pBufIn NULL inLen l must be room here somewhere l pBufIn NewPtr 1ong inLen if SerSetBuf refAIn pBufIn inlen tbox SerSetBuf error load file and send fload refAIn refbout main setupportt refIn ref0ut short refIn ref0ut short parity stopbits databits baud char c...

Страница 139: ...s stop20 databits dataa SerReset refIn short baud I parity I stopbitsl databits SerReset refOut short baud I parity I stopbits Idatabits myExit str rc char str int rc printft str rc exit O fload refIn ref0ut load and send a file short refIn refOut char s SFReply reply StringHandle hStr short refNum int rc result code register long pause long logEOF length of file static SFTypeList typeList TEXT st...

Страница 140: ...fNum blogEOF s tbox Could not read file continue printf Bytes read into buffer ld n logEOF FSClose refNum don t need input file now l send s logEOF ref0ut DisposPtr s release buffer l puts Waiting for any response from device for pause TickCountO 30 TickCount pause showIn refIn SFGetFile pass where OL 1 typelist OL breply send s logEOF refOut char s long logEOF short ref0ut unsigned short loops 1 ...

Страница 141: ... input port ld n count if FSRead refin count text I tbox Yan t read input port buffer return write text to screen write 1 text int count for pause TickCountO 60 TickCount pause else tbox No bytes at input port tbox txt char txt Rect r register long pause SetPort thePort r thePort portRect OffsetRect hr r left r top InsetRect 6r r bottom r top 2 r right r leftl 2 TextBox txt long strlen txt hr teJu...

Страница 142: ... high quality products to meet your needs Did you find deficiencies Please comment on the completeness clarity and organization Did you find errors in the manual If so please give the page number and a description of the error Thank you for your help Name Title Company Name Number Street City State Zip Phone Mail to Technical Publications National Instruments 12 109 Technology Blvd Austin TX 78727...

Отзывы: