MVME5100 Single Board Computer Programmer's Reference Guide

Command Types:
Functional Description
Table 2-7 shows which types of PCI cycles the slave has been designed to
accept.
Table 2-7. 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
Addressing
The PCI 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 forces the PCI Slave to issue a disconnect. During all read cycles,
the PCI Slave returns an entire word of data regardless of the byte enables.
During I/O read cycles, the PCI Slave performs integrity checking of the
byte enables against the address being presented and assert SERR* in the
event there is an error.
http://www.motorola.com/computer/literature 2-23
2