User`s guide

The XMI
2.4.2 Command Cycles
During XMI command cycles, commander nodes initiate XMI
transactions. The commander drives its commander ID on XMI
ID<5:0> L and drives command information on D<63:0> L, as shown
in Figure 2–7 and Figure 2–8.
Figure 2–7 Command Cycle Format for a Data Transaction
6
3
6
0
5
9
5
8
5
7
4
8
4
7
3
2
3
1
3
0
2
90
MASK ADDRESS<29:0>
I/O
COMMAND ADDRESS<39:30> LENGTH
msb−p169−89
MBZ
Figure 2–8 Command Cycle Format for an Interrupt Transaction
6
3
6
0
5
9
2
0
1
9
1
6
1
50
MUST BE ZERO
msb−p170−89
COMMAND
IPL NODE SPECIFIER
The fields of the command cycle are discussed in the following subsections:
• Command field
• Mask field
• Length field
• Address field
• Interrupt Priority Level field
• Node Specifier field
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