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HP 27130A
ASYNCHRONOUS EVENTS
The host may poll the card or may be interrupt driven by the card for any asynchronous event
which can be detected by the MUX firmware. There are four major categories of events. The
events are listed below in the order of their priority.
highest priority
1.
A break condition was received from the device
2.
Any
of the signal characters received
3.
A data record was received from the device
lowest priority
4.
Transmit buffer is empty
The events may be enabled or disabled by using the WCC, SF 21. The event interrupt is enabled by
setting the corresponding mask bit and disabled by clearing the bit.
If the interrupt mask for an event is disabled, you may poll for the event by using Read Card
Information (RCI), Subfunction (SF) 254.
See the paragraph "Event Block Description" for a detailed description of the event block format
returned to the host.
If all interrupt conditions are disabled, no asynchronous interrupts will occur.
SOLICITED EVENTS
The MUX will generate a solicited event upon completion of a speed sense operation. The event
block contains the "speed sense completed" event code, the baud rate which was detected, and the
sense of the parity bit in the carriage return character.
Because this event is solicited, it cannot be masked nor polled.
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