Chapter 3 - MACSI Host Interface

Command Options

No special options are available for this command. Refer to Common IOPB structures for defined options.

Return Status

There are not particular errors currently defined for this IOPB.

Control Flags

Table 3-35. Control Flags

Control Flags

Offst

15

14

13

12

11

10

9

8

7

6

5

4

3

2

1

0

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

0x06

 

 

 

 

 

 

 

 

 

 

 

 

 

 

MIE

MEN

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Enable Multiple Completions (MEN)

Setting this bit enables posting of multiple commands completions. Issuing the command with this bit cleared disables multiple command completions.

Interrupt on Multiple Completion (MEI)

Setting this bit causes the controller to issue an interrupt to the host when posting a multiple command completion. Not setting this bit prevents any interrupt from being posted, requiring the host to poll the Command Response Block for returned completions.

Group Interrupt Level / Vector

This field specifies the VMEbus interrupt level and vector to be used when posting back multiple command completions. These values will override any values specified in the individual IOPBs being returned.

Minimum Group Count

This field is ignored.

Maximum Group Count

This field specifies the maximum number of IOPBs to be returned per completion. For the definition of the returned structure, please refer to the System Interface section of this chapter.

A maximum of 4 entries will fill the Returned IOPB area. 13 overwrites the Configuration Status Block, and 24 fills the remainder of short I/O. Setting this value any less than 24 will significantly constrain the performance of the controller.

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