Upon Termination
When When of Operation at I/O Subch
Deferred Is Is Ctrl I/O Condition Code Idle Working Subch Unit Dev
Deferred
condition code 1 Deferred* condition code 3 Explanation:
After or RIO or
during When Command SIO or
Retry or SIOF& Is Chaining Executed C- C- When
When When I/O When CLRIO Is HIO or Inter- TIO Is Executed HDV Is ruption
Executed + Executed Occurs S S" S S S C The channel can create a deferred-condition-code indication as a result of and subsequent to
the execution of the designated instruction. In the case of CLRIO, the indication is created
at the time the instruction is executed. The indication is not created as a result of the SIO instruction. In all other cases, the creation of the indication generates an interruption
condition. S The deferred-condition-code indication is stored in the CSW at the designated time. * When the CSW is stored, it contains zero unit status. The deferred condition code that is indicated in the CSW can also be the result of CLRIO terĀ­
minating a pending I/O operation that was initiated by means of SIOF executed independent of
the device, or by terminating a suspended I/O operation. The deferred condition code that is indicated in the CSW can be the result of HDV or HIO terminating a pending I/O operation that was initiated by means of SIOF executed independent
of the device, or by terminating a suspended I/O operation.
+ The entries in this column apply only when the CLRIO function is executed. When CLEAR I/O causes the TIO function to be executed, the entries in the TIO column apply.
& When executed as SIO When executed independent of the device - Applies only to RIO or SIOF executed independent of the device
Hote: The absence of an entry indicates that no deferred condition code is created or stored.
Contents of the Deferred-Condition-Code Field CCW Address
When the CSW is formed to reflect the
progress of the I/O operation at the
subchannel, the CCW address is normally
8 higher than the address of the last CCW used in the operation.
The figure "Contents of the CCW-Address Field in the CSW" lists the contents of
the CCW-address field for all situations
that can cause the CSW to be stored.
They are listed in order of priority;
that is, if two situations occur, the CSW appears as indicated for the situĀ­
ation higher on the list. When a CSW has been stored and the situation exists
that a command-retry request has been
recognized but the CCW has not been
re-executed, the "last-used CCW + 8" is
the CCW that is to be retried. Chapter 13. Input/Output Operations 13-75
Situations I/O instruction issued when
channel logout-pending Channel-control check
Status stored by START I/O or
START I/O FAST RELEASE
Status stored by HALT I/O or
HALT DEVICE Invalid CCW-address spec in transfer in channel (TIC) Invalid CCW address in TIC Invalid CCW address generated
Invalid command code, CCW format, IDAW-address speciĀ­
fication, or count
Invalid data address, invalid
IDAW address, or IDAW speciĀ­
fication
Invalid sequence -2 TICs Invalid key on CCW fetch
Invalid key on data or IDAW
access Chaining check
Termination under count control
Termination by I/O device
Termination by HALT I/O or
HALT DEVICE Termination by CLEAR I/O Suppression of command
chaining due to unit check,
attention, or unit exception
with device end, channel end,
or control-unit end
Termination on command
chaining by busy, attention,
unit check, or unit exception
Deferred condition code 1 or 3 PCI flag in CCW Interface control check Channel end after HALT I/O or
HALT DEVICE on selector
channel (and, depending on
design of the subchannel, on
block-multiplexer channel) Channel end after CLEAR I/O Control-unit end
Device end
Attention
Busy Status modifier Channel-available interruption Contents of the CCW-Address Field Contents of Field Zero Unpredictable
Unchanged
Unchanged
Address of TIC + 8
Address of TIC + 8
First invalid CCW address + 8
Address of invalid CCW + 8
Address of current CCW + 8
Address of second TIC + 8
Address of protected CCW + 8
Address of current CCW + 8
Address of last-used CCW + 8
Address of last-used CCW + 8
Address of last-used CCW + 8
Address of last-used CCW + 8
Address of last-used CCW + 8
Address of last CCW used in
the completed operation + 8
Address of CCW specifying
the new operation + 8
Address of CCW specifying
the new or suspended opĀ­
eration + 8
Address of CCW that conĀ­
tained the last recognized PCI flag + 8, or address of CCW which has subsequently
become current + 8. When
the suspended bit (bit 4) of
the CSW is stored as one,
the address stored is the
address of the CCW containĀ­
ing the S flag + 8.
Unpredictable Zero Zero Zero Zero Zero Zero Zero Zero in the CSW 13-76 System/370 Principles of Operation
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