Lecroy WaveSurfer 3054 4-channel oscilloscope, Digital Storage oscilloscope, WaveSurfer 3054 User Manual

Product codes
WaveSurfer 3054
Page of 305
P
A R T  
O
N E
:
 
A B O U T
 
R E M O T E
 
C O N T R O L          
16
  
ISSUED: February 2005
 
WM-RCM-E Rev D
 
•  EOI (End Or Identify): This line has two purposes: The talker uses it to mark the end of  a message 
string. The controller uses it to tell devices to identify their response in a parallel poll (discussed later 
in this section). 
I/O BUFFERS 
 The oscilloscope has 256-byte input and output buffers. An incoming program message is not decoded before 
a message terminator has been received. However, if  the input buffer becomes full (because the program 
message is longer than the buffer), the oscilloscope starts analyzing the message. In this case, data transmission 
is temporarily halted, and the controller may generate a timeout if  the limit was set too low. 
USE IEEE 488.1 STANDARD MESSAGES 
The IEEE 488.1 standard specifies not only the mechanical and electrical aspects of  the GPIB, but also the 
low-level transfer protocol. For instance, it defines how a controller addresses devices, turns them into talkers 
or listeners, resets them, or puts them in the remote state. Such interface messages are executed with the 
interface management lines of  the GPIB, usually with ATN true. 
All these messages except GET are executed immediately upon receipt. 
The command list in Part Two of  this manual does not contain a command for clearing the input or output 
buffers or for setting the oscilloscope to the remote state. 
 
NOTE: In addition to the IEEE 488.1 interface 
message standards, the IEEE 488.2 standard 
specifies certain standardized program messages, 
i.e., command headers. They are identified with a 
leading asterisk * and are listed in the System 
Commands section. 
This is because such commands are already specified as IEEE 488.1 standard messages. Refer to the GPIB 
interface manual of  the host controller as well as to its support programs, which should contain special calls for 
the execution of  these messages. 
The following description covers those IEEE 488.1 standard messages that go beyond mere reconfiguration of  
the bus and that have an effect on X-Stream DSO operation.