Some steering wheel control button needs common increasing data both at Down Button Message and Up Button Message.
This option is used to give common increasing data both for Down and Up Button Messages.

Example:
Idle Message is
Dur: 0 Len: 2 ID:0500 Data:AB CD
Down Button Message is
Dur: 0 Len: 4 ID:0683 Data:04 00 20 0D
Check on Use Idle Message as Up Message

When the button is pressed and released, the messages are sent to the radio though BSGc like below.

Len: 4 ID:0683 Data:04 4E 20 0D
Len: 2 ID:0500 Data:AB 4F
Len: 4 ID:0683 Data:04 50 20 0D
Len: 2 ID:0500 Data:AB 51
Len: 4 ID:0683 Data:04 52 20 0D
Len: 2 ID:0500 Data:AB 53
….

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