Functional Description
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2-15
2
Command Types:
The table below shows which types of PCI cycles the slave has been
designed to accept.
Addressing:
The slave will accept any combination of byte enables during read or write
cycles. During write cycles, a discontinuity (for example, a ‘hole’) in the
byte enables will force the slave to issue a disconnect. During all read
cycles, the slave will return an entire word of data regardless of the byte
enables. During I/O read cycles, the slave will perform integrity checking
of the byte enables against the address being presented and assert SERR*
in the event there is an error.
Table 2-3. PCI Slave Response Command Types
Command Type
Slave Response?
Interrupt Acknowledge
No
Special Cycle
No
I/O Read
Yes
I/O Write
Yes
Reserved
No
Reserved
No
Memory Read
Yes
Memory Write
Yes
Reserved
No
Reserved
No
Configuration Read
Yes
Configuration Write
Yes
Memory Read Multiple
Yes
Dual Address Cycle
No
Memory Read Line
Yes
Memory Write and
Invalidate
Yes