User`s manual

siop_init (Firmware Initialization Structure)

SBCSCSI/D1 B-19

The following table lists the SCLK rate on Motorola VMEmodules:

snoopmode

The SIOP has snoop control output lines which are compatible with the snoop

control inputs of the MC68040 and MC88110. The user initializes this field to

the snoop control mode in which the SIOP is to operate. Recommended

settings for the SBCs are indicated with a Ò*Ó in the table below.

Note

In the table above, * = recommended setting.

reloctbl

The user initializes this field to the globally defined value of the relocation

table (extern RELC relocation[]) which is created by the preprocessor

to the NCR SCRIPTS compiler.

Table B-4. SIOP Clock Rates for VMEmodules

VMEmodule MPU Clock SIOP Clock

MHz MHz Hz

167

25 50 50000000 (0x02FAF080)

187

167

33 66 66666666 (0x03F940AA)

187

197 50 50 50000000 (0x02FAF080)

Table B-5. Snoop Control Modes

Bit 1 Bit 0

Requested Snoop Operation

MVME162/

166/167/197

MVME187

Read Access Write Access

0 0 Inhibit Snooping Inhibit Snooping

0 1 Supply Dirty Data

and Leave Dirty

Sink Byte/Word/Long Data

1 0 Supply Dirty Data

and Mark Invalid

Invalidate Data

1 1 Reserved (Snoop

Inhibited)

Reserved (Snoop Inhibited)