Agilent Technologies E1406A, Руководство пользователя и руководство по программированию SCPI

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Table Format
The format of the commander/servant hierarchy table is shown in Table 2-5.
Table 2-5. Commander/Servant Hierarchy Table Format
Valid Flag/
Number of Modules
Laddr Cmdr Laddr Sec Addr
Laddr Cmdr Laddr Sec Addr
• • •
Laddr Cmdr Laddr Sec Addr
The table parameters are:
•
Valid Flag (1/0) 1 indicates the table is valid and the modules
should be configured accordingly. 0 (zero) will cause an error
message (Error 38). Valid Flag is part of the table header and is
represented by the upper eight bits of the header word.
•
Number of Modules (1 - 254) is the number of entries in the table.
Number of Modules is part of the table header and is represented by
the lower eight bits of the header word.
•
Laddr is the logical address of the module which is assigned a new
commander or new secondary GPIB address. Field is one word.
•
Cmdr Laddr is the logical address of the commander to which the
module specified by Laddr is assigned. If -1 is specified, the
module is not assigned to a commander. Field is one word.
•
Sec Addr (1 - 30) is the secondary GPIB address assigned to the
module specified by Laddr. If -1 is specified, the secondary address
is assigned by default. Field is one word.
Determining the
Table Size
The commander/servant hierarchy table has a one word header and three one
word fields. The amount of RAM allocated with
DIAGnostic:NRAM:CREate is
specified in bytes. Since one word is two bytes, the amount of RAM to
allocate is computed as:
2 + 6(N)
where N is the number of modules to be configured. For example, to assign
three modules to a particular commander, the table size would be:
2 + 6(3) = 20 bytes
DIAGnostic:NRAM:CREate
would be executed as:
OUTPUT @E1406;"DIAG:NRAM:CRE 20"
40 Configuring the Agilent E1406A Command Module Chapter 2