TOS9213S/ TOS9213AS
7-7
7.3
Messages and Terminators
This section explains the terms used for communication between the computer (con-
troller) and the tester (device). See Fig. 7-3.
Fig.7-3
Messages and terminators
7.3.1
Messages
Commands sent from the computer to the tester are referred to as “program mes-
sages.” Responses sent from the tester to the computer are referred to as “response
messages.”
Each message is composed of a program-header block and a data block.
Program messages
Program messages are either “command messages” or “query messages.”
Command messages are used to execute specific functions of the tester and to
change settings.
Query messages are used to inquire about the settings and status of the tester.
Command
program
header
Query
program
header
Program
header
Response
program
header
Response
data
Program
data
Data
Program message
Command
message
Query
message
Program
-message
terminator
Response
-message
terminator
Response
message
Controller
Controller
Device
Device
