Agilent Technologies E1406A, User'S Manual And Scpi Programming Manual

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Reserving A24/A32
Address Space
As previously mentioned, the resource manager cannot determine when
VME devices have been installed in the system. To prevent the resource
manager from allocating A24/A32 addresses intended for VME devices to
VXIbus devices, the address allocation table is used. The A24/A32 address
allocation table is also used to assign different addresses to VXIbus devices
other than those (default) addresses assigned by the resource manager
during power-on.
The A24/A32 Address
Allocation Table
The A24/A32 address allocation table is created and stored in the command
module as follows:
1. Table space in the command module’s non-volatile user RAM is
made available by allocating a segment of RAM with the command:
DIAGnostic:NRAM:CREate < size >
2. Reset the command module. NRAM is created during the boot-up
process:
DIAGnostic:BOOT:WARM
3. The location (starting address) of the table in RAM is determined
with the command:
DIAGnostic:NRAM:ADDRess?
4. Data is downloaded into the table with the command:
DIAGnostic:DOWNload < address >, < data >
5. The table is linked to the appropriate algorithm in the command
module processor with the command:
VXI:CONFigure:MTABle < address >
Table Format
The format of the A24/A32 address allocation table is shown in Table 2-6.
Table 2-6. A24/A32 Address Allocation Table Format
Table Format
Memory Record
Format
Valid Flag/
Number of Records
Laddr
Address Record #1 Frame ID Addr space
Address Record #2 Base addr
•
Memory size
•
Address Record N
48 Configuring the Agilent E1406A Command Module Chapter 2