Initiate I/O (IIO)/OP=94


OP AF BF A Address

OP = 94

AF Size of the I/O descriptor. AF can be indirect. AF can specify a literal.

BF Channel number. BF can be indirect. BF can specify any octal value from 00 to 77 (37 for B2900/B3900).

A Address Address of the memory location containing an I/O Descriptor.

Note This is a privileged instruction. The base must equal zero.
Note This instruction is obsolete.


The IIO instruction causes the I/O Translator to read a Data Link Processor descriptor from the location specified by the A Address. The IOT sends the descriptor to the channel number specified in the BF. It also stores the Begin and End address of the data field in scratchpad memory of the channel.

Comparison Flags

The comparison flags are unchanged.

Overflow Flag

The overflow flag is unchanged.

instructions/iio.txt · Last modified: 2018/03/10 16:02 (external edit)
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