Quantum Data 881 - Manual (Page 407)

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6. Monitor the effects of the corrupt bit test using the ACA. Refer to “ To monitor the CEC
bus (channel): ” on page 492 for instructions on monitoring the commands through the
ACA.
Message acknowledgement tests
You can simulate a condition where a message is improperly acknowledged. You can set
which conditions the 882 will not acknowledge a message. There are four places where
the message can be not acknowledged:
• Header of a directed message
• Data block of a directed message
• Header of a broadcast message
• Data block of a broadcast message
When a directed message is normally acknowledged the acknowledging device pulls the
CEC bus low. In order to not acknowledge a message the target device will not pull the
CEC bus low. When a broadcast message is normally acknowledged the acknowledging
device(s) leave the CEC bus high. In order to not acknowledge a broadcast message the
listening device will pull the CEC bus low.