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8 notification/request message block (nm) – Micromod MOD: 1800P - MOD 30ML Identity Module (Version 2) Algorithms, Tables and Sequential Logic Functions User Manual

Page 71

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Logic Functions - Book 2

NOTIFICATION/REQUEST MESSAGE BLOCK

8-63

8.8

NOTIFICATION/REQUEST MESSAGE BLOCK (NM)

The notification/request message block is used to send a single message over the ICN to the
operator and possibly request an answer from the operator. The message actually resides in
the operator’s display device and shows up as text on the display.

The message can be used to alert the operator to certain conditions relating to the state or
progress of the process. This message could advise the operator to perform certain manual
tasks at the terminal or manually, directly to the process.

The message may request process data from the operator that other function blocks require
but cannot obtain from the instrument database. Then the operator writes the requested data
to the notification/request block through the terminal. The block can be configured to wait a
specified maximum time for a response. A separate notification/request message block must
be configured for each message on the ICN to the terminal.

Block outputs are the requested data, message unacknowledged, active, and timed out flags,
and quality information. A functional block diagram of a notification/request message block is
shown in Figure 8-36. The display, which is used to configure the notification/request
message block, is shown in Figures 8-37 and 8-38.