Programming instructions
Table Of Contents
- Contents
- Title Page
- Chapter 1 Introduction to Programming
- Chapter 2 Programming Getting Started
- Chapter 3 Programming over HP-IB
- Chapter 4 Programming over RS-232-C
- Chapter 5 Programming and Documentation Conventions
- Chapter 6 Status Reporting
- Figure 6-1. Status Reporting Overview Block Diagram
- Table 6-1. Status Reporting Bit Definition
- Status Reporting Data Structures
- Status Byte Register (SBR)
- Service Request Enable Register (SRER)
- Trigger Event Register (TRG)
- Standard Event Status Register (SESR)
- Standard Event Status Enable Register (SESER)
- User Event Register (UER)
- Local Event Register (LCL)
- Operation Status Register (OPR)
- Limit Test Event Register (LTER)
- Mask Test Event Register (MTER)
- Histogram Event Register (HER)
- Arm Event Register (ARM)
- Error Queue
- Output Queue
- Message Queue
- Key Queue
- Clearing Registers and Queues
- Figure 6-3. Status Reporting Decision Chart
- Chapter 7 Installing and Using the Programmer's Reference
- Chapter 8 Programmer’s Quick Reference
- Warranty
- Index
Receiving Information from the Instrument
After receiving a query (command header followed by a question mark), the
instrument interrogates the requested function and places the answer in its
output queue. The answer remains in the output queue until it is read or
another command is issued. When read, the answer is transmitted across the
interface to the designated listener (typically a controller). The input
statement for receiving a response message from an instrument’s output
queue typically has two parameters; the device address, and a format
specification for handling the response message. For example, to read the
result of the query command :ANALOG1:COUPLING? you would execute the
HP BASIC statement:
ENTER <device address> ;Setting$
where <device address> represents the address of your device. This would
enter the current setting for the channel one coupling in the string variable
Setting$.
All results for queries sent in a program message must be read before another
program message is sent. For example, when you send the query
:MEASURE:RISETIME?, you must follow that query with an input statement.
In HP BASIC, this is usually done with an ENTER statement.
Sending another command before reading the result of the query causes the
output buffer to be cleared and the current response to be lost. This also
causes an error to be placed in the error queue.
Executing an input statement before sending a query causes the controller to
wait indefinitely.
The format specification for handling response messages is dependent on
both the controller and the programming language.
Programming Getting Started
Receiving Information from the Instrument
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