Honeywell 400 Series Hardware Manual page 18

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Readers and Punches
Channel Ready 0000
Attention . 0010
Data Alert 0011
Instruction Rejected 0101
Channel Busy 1000
Channel Absent* 1001
Reade rs Only
Device Busy 0001
Load Operation Complete 0111
Channel Alert* 1010
CPZlOO Punch Only
Intermediate 0110
*NOTE: Channel Absent and Channel Alert are generated by the I/O channel of the G-400
Series. ~
Major status always exists on certain electrical lines in the subsystem. This status changes
only on initiation or termination of an instruction. Substatus exists in the subsystem only
during initiation and after termination of an instruction.
Priority of Status
When two or more major statuses exist simultaneously, the subsystem sends the higher
priority status. For these subsystems, major statuses rank as follows (highest priority
listed first): . '
Channel Absent
Channel Alert
Attention* (Card Jam Only)
Instruction Rejected
Data Alert
Intermediate
Attention" (Other than Card Jam)
Load Operation Complete*
Device Busy* '
Channel Busy
Channel Ready
Instruction Rejected is never stored in the subsystem. This is a transient condition that
is reflected to the processing system only in response to the instruction being rejected.
Reflection of the Instruction Rejected major status never affects the status currently
stored. '
*Attention inhibits existence of Load Operation Complete and Device Busy.
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