IBM Series 1 User Manual page 64

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interface, the device must follow through with a dummy
service sequence if it receives a device reset. Device
reset affects the interrupt portion of the poll mechanism
only indirectly by resetting the interrupt request itself at
its source. Recall from the block diagram of channel
sequence interdependencies that an interrupt service
sequence must follow a poll for interrupt without any other
intervening sequence on the service group. Also that the
channel cannot concurrently poll for an interrupt during a
DPC sequence. This means that a device can present an
interrupt request to the interface and then withdraw it on
execution of a device reset or prepare command.
Processor I/O Channel 2-49