MVME5100 Single Board Computer Programmer's Reference Guide

Functional Description
Notes 1. “000” is the default setting in mixed mode.
2. The HEIR setting only covers a small subset of all possible
combinations and the requestors within each group is fixed
and cannot be interchanged with other groups. It is the
responsibility of the system designer to connect the
request/grant pair in a manner most beneficial to their design
goals.
3. All other combinations in the HEIR setting not specified in the
table are invalid and should not be used.
Arbitration parking is programmable by writing to the “PRK” field of the
PCI arbiter control register. Parking can be programmed for any of the
requestors, last requestor or none. The default setting for parking is “Park
on HAWK”. Table 2-12 describes all available settings for the “PRK”
field.
Table 2-12. Arbitration Setting
PRK setting Function
0000 Park on last requestor
0001 Park on PARB6
0010 Park on PARB5
0011 Park on PARB4
0100 Park on PARB3
0101 Park on PARB2
0110 Park on PARB1
0111 Park on PARB0
1000 Park on HAWK
1111 Parking disabled
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