Multiple completed returned iopb structure, Command tag port work queue number transfer count – Interphase Tech CONDOR 4221 User Manual

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Chapter 3 - MACSI Host Interface

64

Multiple Completed Returned IOPB Structure

When multiple commands are returned from the controller to the host with a single interrupt, the following structure
is used to return individual commands, starting in the location of Short I/O normally used for the returned IOPB, and
continuing for a maximum of 24 entries.

Table 3-10. Multiple Completed Returned IOPB Structure

Note: Port and Transfer Count fields are valid only if the posted element is a receive.

Command Tag

This field contains the command tag associated with the original command specified in the by the host in the Command
Queue entry.

Port

For receives only, this field specifies the port on which in-coming frame was received. This field is not valid for
transmits
.

Work Queue Number

This field contains the work queue number provided by the host in the original Command Queue entry.

Transfer Count

For receives only, this field specifies the size of the received frame subject to the same restriction as the returned frame
size parameter in the normal receive IOPB
: you must subtract 4 from this value to get the actual number of bytes
transferred. This field is not valid for transmits.

Multiple Completed Returned IOPB Structure

Addr

15

14

13

12

11

10

9

8

7

6

5

4

3

2

1

0

0x740
0x742

Command Tag
(4 Bytes)

0x744

Port

Work Queue Number

0x746

Transfer Count

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