Functional Description

Command Types

Table 2-4shows which types of PCI cycles the slave has been designed to accept.

Table 2-4. Command Types — PCI Slave Response

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

 

 

Addressing

The slave will accept any combination of byte enables during read or write cycles. During write cycles, a discontinuity (i.e., 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.

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Motorola MVME2300 Series manual Command Types PCI Slave Response, Addressing, Command Type Slave Response?