Dynapro Technologies Dynapro ET TCS, Application Developer'S Manual

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For example, if a <BEL> code (ASCII 07 hex) is received from the host, and default character
font mapping is in effect, the Communication Monitor displays
L,
but the beeper is not sounded.
Two types of control codes are both displayed and acted on:
•
Stall and unstall codes continue to control the data flow between the host and the TCS. See
Chapter 2 for details.
•
Multidrop communications protocol codes continue to establish and disconnect the
communication link.
With these two exceptions, the functional state of the TCS remains as when the Setup Screen is
initially entered.
If a command sequence is only partially received when the Setup Screen is entered, the TCS does
not act on the command upon entering the Communication Monitor. Instead, when the
Communication Monitor is entered, the partial command sequence is canceled and does not
affect TCS functionality
When Local Echo Mode is in effect, codes that would normally cause characters to be echoed to
the display are shown as they cross the communication link, but are not locally echoed.
Therefore, the resulting character is shown only once on the Communication Monitor.
When Local/Remote Mode is set to local, communication with the host is suspended and no
codes are translated for display within the Communication Monitor. If this happens, a special
message is displayed as follows:
LOCAL MODE - Communication Suspended
If this message is displayed, press the Setup key and change Local/Remote Mode to Remote.
When the Communication Monitor is entered, the Standard Character Set is automatically
selected, regardless of the state of the Select Character Set command. Within the Communication
Monitor, characters representing the codes corresponding to the Standard Character Set are
displayed as received and are never shifted out to the Extended Character Set. Exiting the
Communication Monitor restores the previous state of the Select Character Set command, and
codes can once again be shifted out to the Extended Character Set.
While the Communication Monitor is active, all codes pass through the TCS input buffer,
whether they are generated by the TCS or received from the host. As the input buffer fills, the
TCS may stall the host as described in Chapter 2. While the host is stalled, keyboard and touch
panel entries continue to generate codes, so the input buffer may fill to overflowing. In this case,
the TCS continues to send codes to the host, but is unable to display their character
representations on the Communication Monitor. Instead, the Communication Monitor displays a
Buffer Overflow error character
(
B
O
).
Normally only the host can cause such a buffer overflow
error; the TCS sends codes into its own input buffer only during Communication Monitor
operation.
The cursor appears as a slow-blinking block during the Communication Monitor session. Exiting
the Communication Monitor to the Setup Screen restores the
cursor to its previous characteristics.