HP 7470A Owner's manual

INTERFACING
AND
PROGRAMMING
MANUAL
HP 7470A
Graphics Plotter
RS 232 C/CCITT V24
DESIGNED FOR
SYSTEMS

The United States Federal Communications Commission
(in 47CFR 15.838)has specified that the following notice
be brought to the attention of users ofthis product.
FEDERAL COMMUNICATIONS COMMISSION
RADIO FREQUENCY INTERFERENCE
STATEMENT
“Thisequipmentgeneratesand usesradiofrequencyenergyand
ifnot installed and used properly, that is, instrict accordance with
the manufacturer's instructions, maycause interference to radio
and television reception. it has been type tested and found to
comply with the limits for a Class B computing device in
accordance withthe specifications inSubpart J of Part 15of FCC
Rules, which are designed to provide reasonable protection
against such interference in a residential installation. However.
there is no guarantee that interference will not occur in a
particular installation. lfthis equipment does cause interference
to radio or television reception, which can be determined by
turningtheequipmentoffand on,the useris encouragedtotryto
correct the interference by one or more of the following
measures:
—reorient the receiving antenna
—relocate the computer with respect to the receiver
—move the computer away from the receiver
—plug the computer into a different outlet so that computer and
receiver are on different branch circuits.
Ifnecessary, the user should consult the dealer or an experienced
radio/television technician for additional suggestions. The user
may find the following booklet prepared by the Federal Com
munications Commission helpful:
‘Howto Identify and Resolve Radio TV Interference Problems‘.
This booklet isavailable from the USGovernment Printing Office,
Washington, DC 20402, Stock No. 004 000 00345 4."

INTERFA(§1\1\JIG 1C:1PpZ_47%;\tt
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PROGRAMMING
M RS 232 C/CCITTV.24
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SYSTEMS
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@1982,1984, by Hewlett Packard Comp
16399W. Bernardo Drive, San Diego, CA 92 1899

Manual Summary
Chapter 1: Getting Started
Contains information concerning manual usage, a description of the
plotter, its interfaces, the HP—GLlanguage, and three instructions.
Chapter 2: Establishing Boundaries and Units
Explains the concept of plotting area, plotter and user units, scaling,
and the instructions used to set and output the scaling points and
window, and to scale the plotting area.
Chapter 3: Controlling the Pen and Plotting
Describesthe instructions for pen control and vector plotting.
Chapter 4: Enhancing the Plot
Describesinstructions for drawing tick marks and differentiating traces.
Chapter 5: Labeling
Describes the instructions used in labeling to set direction, size, and
slant of characters, as well as instructions for character set and label
terminator selection and for designing your own characters.
Chapter 6: Digitizing
Describes the instructions used to digitize with the plotter and demon
strates how to check for the presence of a digitized point.
Chapter 7: Obtaining Information fromthe Plotter
Describes the instructions used to obtain information about pen posi
tion, errors, and capabilities ofthe plotter.
Chapter 8: Putting the Commandsto Work
A step by—stepexample illustrating the procedures to be followed to
draw labels and plot data using HP GLinstructions.
Chapter 9: HP IB Interfacing
Summarizes operation ofthe plotter with the Hewlett PackardInterface
Bus (HP IB)and explains the methods for addressing and sending and
receiving data over the interface bus.
Chapter 10: RS 232 C/CCITT V.24Interfacing
Describes how to connect the plotter with a terminal and/ or computer,
summarizes the methods for establishing a handshake protocol be
tween the plotter and computer, and explains the devicecontrol instruc
tions that are used to set up and control the handshake protocol.
Chapter 11: HP IL Interfacing .
Describesthe Hewlett Packard Interface Loop(HP IL)and explains the
methods for sending and receiving data overthe interface loop.
Appendix A: An HP IB Overview
Provides an overview of the Hewlett Packard Interface Bus (HP IB).
ii MANUAL SUMMARY

Manual Summary (Continued)
AppendixB: Instruction Syntax
Provides a summary of both HP—GLand device control instructions.
Appendix C: Reference Material
Includes a summary of default conditions, error messages, scaling
equations, NOP instructions, ASCII codes, and character sets.
MANUAL SUMMARY iii

Tableof Contents
Chapter 1: Getting Started . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 1
What You’ll Learn in This Chapter . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 1
HP GL Instructions Covered . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 1
Terms You Should Understand . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 1
How to Use HP 7470 Documentation . . . . . . . . . . . . . . . . . . . . . . . . . 1 2
For First Encounters with the 7470 . . . . . . . . . . . . . . . . . . . . . . . . . 1 3
For First Encounters with HP GL . . . . . . . . . . . . . . . . . . . . . . . . . . 1 3
For Experienced HP GL Programmers . . . . . . . . . . . . . . . . . . . . . 1 3
Understanding Manual Conventions and Syntax . . . . . . . . . . . 1 3
A Brief Look at the 7470 Plotter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 5
The 7470 Plotter’s Instruction Set . . . . . . . . . . .‘. . . . . . . . . . . . . . . . . 1 6
HP GL Syntax . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 6
How to Use the Examples in This Manual . . . . . . . . . . . . . . . . . . . . 1 10
The Default Instruction, DF . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 10
The Initialize Instruction, IN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 11
The Input Mask Instruction, IM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 12
Looking Ahead . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 15
Chapter 2: Establishing Boundaries and Units . . . . . . . . . . . . . . . . . 2 1
What You’ll Learn in This Chapter . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 1
HP GL Instructions Covered . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 1
Terms You Should Understand . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 1
The Plotting Area . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 2
Unit Systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 3
The Plotter Unit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 3
User Units . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 3
Setting the Scaling Points . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 3
Setting P1 and P2 Manually . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 4
The Input P1 and P2 Instruction, IP . . . . . . . . . . . . . . . . . . . . . . . . . . 2 4
The Output P1 and P2 Instruction, OP . . . . . . . . . . . . . . . . . . . . . . . 2 5
The Scale Instruction, SC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 6
The Input Window Instruction, IW . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 9
The Output Window Instruction, OW . . . . . . . . . . . . . . . . . . . . . . . . . 2 10
Advanced Programming Tips . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 11
Chapter 3: Controlling the Pen and Plotting . . . . . . . . . . . . . . . . . . . . 3 1
What You’ll Learn in This Chapter . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 1
HP GL Instructions Covered . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 1
Terms You Should Understand . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 1
1V TABLE OF CONTENTS

Table of Contents (Continued)
Chapter 3: Controlling the Pen and Plotting (Continued)
The Pen Instructions, PU and PD . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 2
The Select Pen Instruction, SP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 2
The Velocity Select Instruction, VS . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 3
The Plot Absolute Instruction, PA . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 4
The Plot Relative Instruction, PR . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 8
Plotting with Variables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 11
The Circle Instruction, CI . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 12
The Arc Absolute Instruction, AA . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 17
The Arc Relative Instruction, AR . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 19
Chapter 4: Enhancing the Plot . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 1
What You’ll Learn in This Chapter . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 1
HP GL Instructions Covered . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 1
The Tick Instructions, XT and YT . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 2
The Tick Length Instruction, TL . . . . . . . ._. . . . . . . . . . . . . . . . . . . . . 4 2
The Symbol Mode Instruction, SM . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 4
The Line Type Instruction, LT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 6
Chapter 5: Labeling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 1
What You’ll Learn in This Chapter . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 1
HP GL Instructions Covered . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 1
Terms You Should Understand . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 1
Plotter Character Sets . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 2
The Designate Standard Character Set Instruction, CS . . . . . . . . 5 3
The Designate Alternate Character Set Instruction, CA . . . . . . . . 5 4
The Select Standard Set Instruction, SS . . . . . . . . . . . . . . . . . . . . . . 5 4
The Select Alternate Set Instruction, SA . . . . . . . . . . . . . . . . . . . . . . 5 5
The Define Terminator Instruction, DT . . . . . . . . . . . . . . . . . . . . . . . 5 6
The Label Instruction, LB . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 7
Labeling with Variables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 9
The Absolute Direction Instruction, DI . . . . . . . . . . . . . . . . . . . . . . . 5 10
The Relative Direction Instruction, DR . . . . . . . . . . . . . . . . . . . . . . . 5 11
Spacing Between Characters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 12
The Character Plot Instruction, CP . . . . . . . . . . . . . . . . . . . . . . . . . . 5 13
The Absolute Character Size Instruction, SI . . . . . . . . . . . . . . . . . . 5 15
The Relative Character Size Instruction, SR . . . . . . . . . . . . . . . . . . 5 16
The Character Slant Instruction, SL . . . . . . . . . . . . . . . . . . . . . . . . . 5 18
TABLE OF CONTENTS V

Table of Contents (Continued)
Chapter 5: Labeling (Continued)
The User Defined Character Instruction, UC . . . . . . . . . . . . . . . . . . 5 19
Parameter Interaction in Labeling Commands . . . . . . . . . . . . . . . . 5 21
Advanced Programming Tips . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 27
Chapter 6: Digitizing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 6 1
What You’ll Learn in This Chapter . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 1
HP—GL Instructions Covered . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 1
Terms You Should Understand . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 1
Preparing Your Plotter for Use as a Digitizer . . . . . . . . . . . . . . . . . . 6 2
The Digitize Point Instruction, DP . . . . . . . . . . . . . . . . . . . . . . . . . 6 2
The Digitize Clear Instruction, DC . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 3 A
The Output Digitized Point and Pen Status Instruction, OD . . . . . 6 3
Digitizing with the 7470 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 4
Manual Method . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 4
Monitoring the Status Byte . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 5
HP—IB Interrupts and Polling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 7
Chapter 7: Obtaining Information From the Plotter . . . . . . . . . . . . . 7 1
What You’ll Learn in This Chapter . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 1
HP—GL Instructions Covered . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 1
Terms You Should Understand . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 1
A Brief Word about Plotter Output . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 2
Notes for an HP IB User . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 2
Notes for an RS 232 C User . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 2
Notes for an HP IL User . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 2
The Output Actual Position and Pen Status
Instruction, OA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 3
The Output Commanded Position and Pen Status
Instruction, OC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 4
The Output Error Instruction, OE . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 5
The Output Factors Instruction, OF . . . . . . . . . . . . . . . . . . . . . . . . . . 7 6
The Output Identification Instruction, OI . . . . . . . . . . . . . . . . . . . . . 7 7
The Output Options Instruction, OO . . . . . . . . . . . . . . . . . . . . . . . . . 7 7
The Output Status Instruction, OS . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 8
Summary of Output Response Types . . . . . . . . . . . . . . . . . . . . . . . . . 7 9
Vi TABLE OF CONTENTS

Table of Contents (Continued)
Chapter 8: Putting the Commands to Work . . . . . . . . . . . . . . . . . . . . . 8 1
What You’ll Learn in This Chapter . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 1
Problem .................................................... 82
Solution . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 2
Setup and Scaling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 2
The Axes and Their Labels . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 3
Adding Color and Emphasis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 5
Plotting Your Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 6
Listing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 9
Advanced Programming Tips . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 10
Filling and Hatching . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 10
Filling a Bar . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 10
Hatching a Bar . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 12
Filling Segments of Pie Charts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 13
Chapter 9: HP IB Interfacing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 1
What You’ll Learn in This Chapter . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 1
HP IB Implementation on the 7470 . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 2
Interface Switches and Controls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 2
Addressing the Plotter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 2
Bus Commands . . . . . . . . . . . . . . . . . . . . . . . . . . . . . , . . . . . . . . . . . . . . . 9 4
Reaction to Bus Commands DCL, SDC, and IFC . . . . . . . . . . . . 9 4
Serial and Parallel Polling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 4
Addressing the 7470 as a Talker or Listener . . . . . . . . . . . . . . . . . . . 9 6
Computers with No High Level I/O Statements . . . . . . . . . . . . . 9 6
Computer with High Level I/O Statements . . . . . . . . . . . . . . . . . 9 6
Sending and Receiving Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 7
Computer to Plotter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 7
Plotter to—Computer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 10
Chapter 10: RS 232 C/CCITT V.24 Interfacing . . . . . . . . . . . . . . . . . . 10 1
What You’ll Learn in This Chapter . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 1
Setting Up Your RS 232—CPlotter: a Checklist . . . . . . . . . . . . . . . . 10 2
Plotter Environments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 2
Using a Plotter Directly Connected to a
Computer Mainframe or Personal Computer . . . . . . . . . . . . . . 10 2
Using a Plotter in an Environment with a Terminal . . . . . . . . . 10 4
Using the Plotter in a Terminal only Environment . . . . . . . . . . 10 9
Connecting the RS 232 C Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 10
TABLE OF CONTENTS Vii

Table of Contents (Continued)
Chapter 10: RS 232 C/CCITT V.24Interfacing (Continued)
Output Baud Rate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 12
Stop Bits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 13
Transmission Errors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 13
Handshaking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10 14
Software Checking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 17
Xon Xoff Handshake . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10 19
Enquire/Acknowledge Handshake . . . . . . . . . . . . . . . . . . . . . . . . . 10 20
Hardwire Handshake . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 22
RS 232 C Device Control Instructions . . . . . . . . . . . . . . . . . . . . . . . . . 10 22
Command Syntax for Device Control Instructions . . . . . . . . . . .10 23
The Plotter On Instruction, ESC . ( or ESC . Y . . . . . . . . . . . . . . .10 24
The Plotter Off Instruction, ESC . ) or ESC . Z . . . . . . . . . . . . . . . . 10 24
The Set Plotter Configuration Instruction, ESC . @ . . . . . . . . . . . .10 25
The Output Buffer Space Instruction, ESC . B . . . . . . . . . . . . . . . . 10 26
The Output Extended Error Instruction, ESC . E . . . . . . . . . . . . . .10 27
The Set Handshake Mode 1 Instruction, ESC . H . . . . . . . . . . . . . .10 28
The Set Handshake Mode 2 Instruction, ESC . I . . . . . . . . . . . . . . .10 29
The Abort Device Control Instruction, ESC . J . . . . . . . . . . . . . . . . 10 31
The Abort Graphic Instruction, ESC . K . . . . . . . . . . . . . . . . . . . . . . 10 32
The Output Buffer Size Instruction, ESC . L . . . . . . . . . . . . . . . . . . 10 32
The Set Output Mode Instruction, ESC . M . . . . . . . . . . . . . . . . . . .10 33
The Set Extended Output and Handshake Mode
Instruction, ESC . N . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 34
The Output Extended Status Instruction, ESC . O . . . . . . . . . . . . .10 38
The Reset Handshake Instruction, ESC . R . . . . . . . . . . . . . . . . . . . 10 40
Chapter 11: HP IL Interfacing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 1
What You’ll Learn in this Chapter . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 1
An Overview of HP IL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 1
HP IL Implementation on the 7470 . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 2
Reaction to Interface Commands and Messages . . . . . . . . . . . . . . . 11 3
Addressing the Plotter , . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 3
Sending and Receiving Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 4
Computer to—P1otter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 4
Plotter to Computer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 5
viii TABLEOF CONTENTS