NCR 5977-1000, Руководство пользователя

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5-36 NCR 5977 2x20 Display Programming
Set Display State On
Format
1B 05
Description
This state is used for normal run–time conditions. This operation instructs the firmware
to leave one of the other states and begin performing normal refresh operations. There
may be a slight delay before the display reaches the specified brightness setting when
exiting the Low Power State. This delay should not exceed 1 second from the time the
command is received until the time the display reaches the specified brightness.
Highest priority is given to refresh operations and a lower priority is given to host
communications. Host communications still work, but if a large amount of data is to be
programmed in a very short time frame, it would work faster if the Blank State was
programmed prior to the information transfer.
The Screen Save feature may be in force during the Display On state. This means that
after about five minutes of no new display activity, the Screen Save feature could take
over and cause the display to go blank or begin walking from right to left.
Set Low Power State On
Format 1B 06
Description
This state is used to reduce Retail Display power consumption and extend the life of the
Retail Display. Power is only removed from the display and the display is not refreshed.
The Retail Display controller is still fully operational and continues to accept commands.
This command causes the firmware to blank or turn off the Retail Display. Display data
can be processed while the display is in the Low Power state, but it does not appear
until the Low Power state is changed. The displayed character’s state is preserved so
that upon leaving the Low Power State the display is restored. To leave the Low Power
State, one of the other state commands must be received. This is the default state for the
Retail Display after power–up.