Datalogic GWY-01-PBS-01, Reference Manual

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GWY-01-PBS-01
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4.10 NOTIFICATION MESSAGES
Notification Messages are small host-bound informational packets of data that are issued
by the Gateway when a specified Notification Event (or series of events) occurs within the
Gateway or on the Subnet network. For example, the Gateway can be configured to send the
host a Notification Message when a controller is attached, or removed, or experiences a
problem.
The Gateway stores nine different Notification Messages internally (all of which are enabled
by default). A 16-bit value, called the
Notification Mask , controls which Notification Events
trigger Notification Messages to the host. Bits 00 through 08 in the 16-bit Notification Mask
correspond to the nine possible Notification Messages. The remaining 7 bits (bits 09-15) are
not implemented at this time (default value is zero for each bit).
Notification Messages are enabled by changing the associated bit from zero to one within the
Notification Mask. A bit is either set to “0” (OFF – disabled) or “1” (ON – enabled). When a bit
is turned ON, the related Notification Message will be enabled. The next time the enabled
Notification Event occurs, the corresponding Notification Message will be generated and
immediately delivered to the host.
When a Notification Event occurs it generates a Notification Message which is written to the
Host. Notification Messages include a one-byte value indicating which of the nine possible
Notification Events occurred. Notification Messages also contain a one-byte value that
identifies the affected Node ID.
For Notification Messages, a handshaking scheme of enabling and clearing a specific bit in
the Notification Mask is implemented (as previously explained).
To enable all nine Notification Messages, the 2-byte Notification Mask would read:
0x01FF .
16-BIT NOTIFICATION MASK
Bits
15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
Value
[0] [0] [0] [0] [0] [0] [0] [1] [1] [1] [1] [1] [1] [1] [1] [1]