IORB (I/O Request Block Definition) Macro
The macro generates an IORB (input/output request block).
The block is generated when your program is being assembled. For the layout and contents of an IORB, see Table 1 in this topic.
Offset (In Hex) | Length (In Hex) | Contents |
---|---|---|
0 | 2 | Residual count (same as for a CCB; see Table 1 in the topic Format of the CCB). |
2 | 2 | Transmission information (same as for a CCB; see Table 1 in the topic Format of the CCB). |
4 | 2 | CSW status bits (same as for a CCB; see Table 1 in the topic Format of the CCB). |
6 | 7 | Reserved. |
0D | 3 | CSW address in CSW (same as for a CCB; see Table 1 in the topic Format of the CCB). |
10 | 10 | Reserved. |
The block is an alternative to the CCB: instead of specifying a CCB in the EXCP macro, the address of an IORB is given.
Format
Requirements for the caller
- RMODE:
- 24
Parameters
- CCW=name1
- This operand gives the name of the first CCW used with the IORB. This name must be the same as the name specified in the assembler CCW statement that builds the CCW.
- DEVICE=SYSxxx
- This operand specifies the logical unit for the actual I/O unit with which this IORB is associated.
- DSECT=YES
- If the operand is specified, it should be the only one. Any other
operands that you specify are ignored and an MNOTE is generated by the
assembler.
Specifying DSECT=YES causes the assembler to generate, as a DSECT structure, the IORB and the meaning of its fields.
- ECB=name2
- This operand specifies the address of the ECB to be posted when I/O is
complete. The traffic bit (byte 2, bit 0) of the ECB must have been
cleared before issuing the EXCP macro. The ECB area must be included
in the fix list if the ECB operand is used. Note: If FIXFLAG=(FIXED) is specified, the ECB must have be fixed in storage by a PFIX macro.
- IOFLAG=(option,...)
- A list of options can be specified which apply to I/O interrupt
handling:
- POSTDE
- To indicate that device end is to be posted.
- POSTERR
- To indicate that an irrecoverable I/O error is to be accepted.
- SKIPERP
- To indicate that error recovery by the system is to be skipped.
- FORMAT1
- To indicate that the CCW is a format-1 CCW.