American Magnetics 420 Power Supply Programmer - Manual (Page 95)

Rev. 7 77
Remote Interface Reference
IEEE-488 Configuration
<LF><CR>, or a semicolon ( ; ) as termination characters from an external
computer.
4.3.3 Flow Control Modes
The operator may select between two flow control modes for data transfers
between the host device and the Model 420:
‡ None: Data is sent and received over the interface with no flow
control. When using this mode, avoid sending more than 64
characters without stopping or reading a response.
‡ Software: Also referred to as XON/XOFF. Software handshaking
uses special embedded characters in the data stream to control the
flow. If the Model 420 is asked to return data, it continues data
output until the XOFF character (13 Hex) is received. Once an XOFF
character is received, an XON character (11 Hex) is required for data
transmission to continue.
The Model 420 also sends XON/XOFF when its internal serial port
buffer reaches a “high-water” mark. The host device should suspend
transmission on receipt of an XOFF character from the Model 420,
and resume when an XON character is received.
Note
The XON/XOFF flow control should not be used as a substitute for
command handshaking as documented in paragraph 4.2.4.
XON/XOFF characters are not generated in the case of “input
overflow” errors (error number -303).
4.4 IEEE-488 Configuration
The Model 420 allows the primary IEEE-488 address of the Model 420 to
be configured by the user. See the Comm Setup Submenu description in
paragraph 3.2.4 on page 49 for an illustration of the menu provided for
configuring the Model 420 IEEE-488 address.
4.4.1 Termination Characters
All commands are transmitted and received as ASCII values and are case
insensitive. The Model 420 always transmits <LF> with EOI as the
termination for return data. The Model 420 can accept <CR>, <LF>, or
<LF> with EOI as termination characters from an external IEEE-488
interface. More than one command may be sent before a terminator if each
command is separated with a semicolon ( ; ).