Fluke 1502A 7 Digital Communications Interface

7 Digital Communications Interface

Remote communications allowsan external device, such as a computer, to com-

municatewith the 1502A to obtain measurement data and control its operation.

Communication is accomplished with variouscommands issued to the 1502A

through the RS-232 port or optional IEEE-488 port. A full list of commands is

giveninSection7.3.

7.1 Serial Interface

The 1502A isequipped with an RS-232 serial port. The RS-232 interface is

useful for connectingthe 1502A to most any microcomputer. The RS-232

socketis located on the back panel of the 1502A. Wiringof the interface cable

should be asshown in Figure 5 below. To eliminate noise, the serial cable

should be shieldedwith low re-

sistance between the connector

(DB-9) and the shield.The pro-

tocolfor RS-232 communica-

tions is 8 data bits, 1 stop bit,

and no parity.The RS-232 inter-

faceuses RTS and CTS for flow

control.

7.1.1 Setting the Baud Rate

The 1502A must be set to the

same baud rate as the remote

device.The baud rate of the

1502A can be setto 1200, 2400,

4800, or 9600. The defaultis

2400. The baud rate is set in the

Comm menu. Press the Menu

button (“SEt?” appears) then

press the K/Comm button.The

display will briefly indicate

“SErIAL”, then “bAUd”and

then displaythe current baud

rate. Use the Uand Dbuttons

to increase or decrease the baud

rate then press Enter.The next

parameter in theComm menu,

the serial sample period, will

then appear.

23

7 Digital Communications Interface

Serial Interface

Figure5 Serial Cable Wiring

Contents

Main Rev. 722101 Table of Contents 7 Digital Communications Interface . . . . . . . . . . . . . . . 23 ii 7.3 Remote Commands . . . . . . . . . . . . . . . . . . . . . . . . . 26 8 Calibration Procedure . . . . . . . . . . . . . . . . . . . . . . 35 Page Page 1 Before You Start 1.1 Symbols Used 1.2 Safety Information 1.2.1 Warnings 1.2.2 Cautions 1.3 Authorized Service Centers Page 2 Introduction 3 Specifications and Environmental Conditions 3.1 Specifications 9 3 Specifications and Environmental Conditions Specifications 3.2 Environmental Conditions 4 Quick Start 4.1 Unpacking 4.2 Power 4.3 Connecting the Probe Page 5 Parts and Controls 5.1 Front Panel Buttons 84.981 C 5.2 Rear Panel l 6 General Operation 6.1 Selecting Units 6.2 Parameter Menus 6.3 Menu Lockout Page 6.4 Selecting the Probe Characterization E -04 6.4.3 ITS-90 PRT and Coefficients Page [] () [] 6.4.4 Callendar-VanDusen (RTD) Conversion The RTDconversion uses the Callendar-VanDusen equation: 6.4.5 IPTS-68 Conversion A4 +4.336079 E -04 6.5 Filtering 6.6 Setting the Current 6.7 Power Saver 7 Digital Communications Interface 7.1 Serial Interface 7.1.1 Setting the Baud Rate 7.1.2 Automatic Transmission of Measurements 7.1.3 Time Stamp and System Clock 7.1.4 Duplex Mode and Linefeed 7.2 GPIB Interface 7.2.1 Setting the Address 7.2.2 Setting the Termination Character 7.2.3 Time Stamp 7.3 Remote Commands 7.3.1 Measurement Commands 27 7 Digital Communications Interface Remote Commands Table 6 Command List Page 7.3.2 Probe Characterization Commands 7.3.3 Sample Commands 7.3.4 Communication Commands 7.3.5 Calibration Commands 7.3.6 Other Commands Page 8 Calibration Procedure 8.1 Accessing the Calibration Parameters 8.2 Calibration Procedure 9 Maintenance 10 Troubleshooting 10.1 CE Comments 10.1.1 EMC Directive 10.1.2 Low Voltage Directive (Safety)