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0
2
3
4
5
6
7
Data Address
I
I
Channel Status flags and Ops r - - - - - - - - .
Count
Next CCW Address
Unit Status
l
l
J
Byte 0
Bit 0
Byte 1
Bytes 2 and 3
Byte 2
Bytes 4 and 5
Bytes 6 and 7
Byte 7
Bit 1
Bit
2
Bit 3
Bit
4
Bit
5
Bit
6
Bit
7
Bit
0
Bit 1
Bit
2
Bit 3
Bit 4
Bit 5
Bits 6 and 7
0
0
0
1
1
0
1
1
Bit 0
Bit
1
Bit 2
Bit 3
Bit 4
Bit 5
Bit 6
Bit 7
Bit 7
-· PCI CHK CHNL STATUS: also before channel status is presented acts to indicate that a pending interrupt
- is for a PCI interrupt only and not a Channel End-Device End interrupt.
- Incorrect length record check
(I
LC).
- Program check.
- Protection check.
- Not used.
- Not used.
- Indicates whether the address of the UCW is in the interrupt
Q
table.
- Interrupt pending bit.
- Chain Data flag (CD).
- Chain Command flag (CC).
- Suppress Length Indication (SLI ).
-SKIP flag.
- Programmed Controlled Interrupt flag (PCI ).
- Active Bit; on when commands are being executed or when interrupt pends in interrupt Q table.
- Decoded as follows.
- Count has gone to zero in count field and UCW is waiting for another data transfer request to respond with
channel stop and set up to set ILC in CHNL. Status in GENO.
- Write type command being executed.
- Read type command being executed.
- Set when a channel stop is given and will indicate to GENO to signal a possible I LC.
- Data Address during command execution
- Device Status at Command End.
- Not set by ICA
- Status Modifier
- Not set by ICA
- Not set by ICA -- Busy set by CC to SIO, TIO
- Channel End
l
D
.
E d
f
Always presented together in ICA
-
ev1ce
n
- Unit Check
- Unit Exception
- Count Field
- Next CCW Address
- On when ICA UCW is not operational (tested in DCLA)
Figure 1-70.
!CA UCW Format
2025 FEMM (7/69) 1-81
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