Input/Output Error Data Block (IEDB) Fields

The system uses the IEDB to provide extended error information, and for zHPF the failing storage address. The IEDB has two versions:

The version 1 IEDB is 48 bytes.
The version 2 IEDB is 96 bytes. This is the recommended version for zHPF channel programs.

You provide an IEDB by setting its address in an IOBE. Set reserved fields to X'00'. The system moves the sense bytes to IEDBSNS. If fewer than 32 sense bytes are available, there might be residual data. Refer to Requesting Extended Error Information for more information on using the IEDB. Start of change

Figure 1. Format of an IEDB, Mapped by the IOSDIEDB Macro

Table 1. IEDB Structure Mapping
Offset	Length or Bit Pattern	Name	Description
0 (X'0')	4	IEDBID	Eye catcher. Must be "IEDB"
4 (X'4')	1	IEDBVERS	Version. The version 1 IEDB is 48 bytes. The version 2 IEDB is 96 bytes. This is the recommended version for zHPF channel programs. For version 1, the macro defines IEDBVRSC as the version constant. For version 2, the macro defines IEDBVRS2 as the version constant.
5 (X'5')	1	IEDBFLG1	Flags field.
	1... ....	IEDBBDSN	The sense data is invalid and begins with X'10FE'.
	.1.. ....	IEDBFSAV	The failing storage address (IEDBFSA) is valid.
	..xx xxxx		Reserved.
6 (X'6')	1	IEDBCOD	Original I/O completion code prior to EXCP or EXCPVR changing it. This is the same format as the ECB completion code byte.
7 (X'7')	1		Reserved.
8 (X'8')	32	IEDBSNS	Sense bytes.
8 (X'8')	1	IEDBSNS00	Sense byte 0.
9 (X'9')	1	IEDBSNS01	Sense byte 1.
(Fields IEDBSNS02 to IEDBSNS31 define sense bytes 2 to 31.)
40(X'28')	4		Reserved.
44(X'2C')	4	IEDB2CSW	Virtual CCW address pointing after the last CCW executed by the control unit. The system sets this only if all of the following are true: (1) EXCP or the user set IOBEP on to allow prefetching of CCWs and data, (2) the user set IOB2CSWS on (two channel status words), (3) the control unit was executing ahead of the channel, (4) the control unit detected an error and (5) the control unit reported the failing CCW. The system never clears this field.
48(X'30')	8	IEDBFSA	The failing storage address for channel control checks and channel data checks. For zHPF channel programs, a failing storage address may also be provided for program checks and protection checks. This field is valid only if IEDBFSAV is on.
56(X'38')	40		Reserved.