Status Bytes (Loitial And Ending) - IBM System/360 Field Engineering Manual

2702
TRANSMISSION CONTROL (Continued)
Status Bytes (Initial and Ending)
Bit
2
3
4
5
6
Name
Description
Attention
(2702
does not set this bit in the status
byte).
Status Modifier Test I/O instruction decoded on initial
selection. Unit busy or machine reset
(power on, manual, or interface reset)
while in initial selection.
Control Unit
End
Busy
Cbannel End
Decode End
Unit Check
Unit Exception
Unit busy or machine reset while in
initial selection.
Unit busy or machine reset while in
initial selection.
No-op decoded during initial selection.
Receive operation in progress when write-
type command is about to be inserted.
End sequence set in a send/receive
operation.
No-op decoded during initial selection.
Receive operation in progress when write-
type command is about to be inserted. End
sequence set in a send/receive operation.
If stacked on initial selection and other
than Test I/0 or No-op.
Parity check on command byte during
initial selection. Invalid command byte
decoded during initial selection. Channel
End and Device End (4 and 5) and one of
the following: not operate, equipment
check, bus-out parity, timeout, overrun,
command reject, and data check. Receive
operation in progress when write-type
command is about to be inserted.
End sequence on a write poll command.
Receive
@
while in sequence 2 of a read
command. Negative answer to poll from
1050 in control mode of a receive opera-
tion.
78 S/:i60 IBM CONFIDENTIAL