- Entry:
- SCHD
- VIT option:
- PSS
- Event:
- Schedule of PAB dispatch
- VIT processing module:
- ISTRACPS
- Control is returned to:
- ISTAPCTS
This trace record shows the schedule of a PAB to be dispatched
and the last work element, if any, that was queued to the PAB. This
entry should be followed shortly by a DSP entry, representing the
PSS dispatch of this PAB. 
- Byte (hex)
- Contents
- 00–03
- Record ID: C"SCHD"
- 04
- ID is the primary address space ID (ASID). This field is 0 if the ASID is greater than X'FF'.
- 05
- Status
- Bit
- Meaning
- xx.. ....
- 0
- ..1. ....
- TPSCHED unconditional
- ...x ....
- 0
- .... 1...
- Registers are saved in the RPH control block.
- .... .x..
- 0
- .... ..1.
- PAB work element queue gate bit (PABWEQG).
- .... ...0
- PAB change bit (PABCHNG) = 0 if the PAB is not scheduled to run.
- .... ...1
- PABCHNG=1 if the PAB is scheduled to run.
- 06
- PAB flag field (PABFLAGS)
- Bit
- Meaning
- 1... ....
- PAB is unconditionally scheduled.
- .1.. ....
- PAB closedown is in progress.
- ..1. ....
- PAB is synchronous.
- ...1 ....
- PAB extension is present.
- .... 1...
- Do not dequeue work element.
- .... .1..
- Do not detach the RPH.
- .... ..1.
- Indicates a very extended PAB.
- .... ...1
- Indicates a slightly extended PAB.
- 07
- PAB flag field (PABFLGS1)
- Bit
- Meaning
- 1... ....
- Switch the PST address of this PAB’s major control block to the new PST address contained in DYPNWPST.
- .1.. ....
- This PAB has a data space extension.
- ..1. ....
- This PAB’s major control block is an FMCB.
- ...1 ....
- PAB can be referenced in PSW disable mode.
- .... 1...
- PAB is persistent.
- .... .1..
- APSTERM/APSINIT FMCB during PAB dispatch.
- .... ..xx
- 0
- 08–0B
- PST address associated with PAB
- 0C–0F
- PAB address
- 10–13
- Address of the issuer of the TPSCHED macro
- 14–17
- PAB work element queue or next dispatchable queue level for a very extended PAB
- 18–1B
- Module name abbreviation (bytes 4, 5, 7, and 8 of the module name) or PAB DVT address (high-order bit of X'18' = 0). For an explanation of the module naming convention, see Using module names to isolate VTAM problems. The module name might be unavailable if the PAB being scheduled is associated with an address space different from the current one.
- 1C–1F
- Request parameter header (RPH) address