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3-3
Section
Screen Display and Notification
295
3-3-2 Finding the Screen Number of the Presently Displayed Screen
The PT has a function to notify the host of the occurrence of a screen switching
event, and the screen number of the new screen when the display screen is
switched by operation at the PT.
The host uses the following method to ascertain the screen switching timing and
the new screen number.
Reading the PT status notify area and the PT status control area
Reading the PT Status Notify Area and the PT Status Control Area
When the screen is switched, it is notified to the following areas.
•
Screen switching timing:
Screen switching strobe in the PT status notify area
•
Screen number of the presently displayed screen:
Screen switch setting word in the PT status notify area
Displayed screen
PC
PT
←
Screen No.
PT status control area
Screen switch setting
Copy memory
table setting
PT status control setting
Reserved for system use
←
Screen switch strobe flag
PT status notify area
Content update memory table
PT status
Reference:
When NT30/620 compatible mode is being used, the current screen number oc-
cupies the first word of the PT status notify area and the word containing the PT
status notify bits is shifted down one word. (Refer to page 441.)
The PT status notify area and the PT status control area must be allocated to a
word in the host, accordingly, no special settings are required for reading the sta-
tus.
Follow the procedure indicated below to check the screen switching executed by
operation at the PT.
Reading Screen Switching Timing
The bit for notifying the PT status (PT status notify bit) is provided at the second
word (word m + 1) from the beginning of the PT status notify area.
0
0
1 (ON)
Run
Low
Printing
Off
Open
Open
Open
0 (OFF)
Stop
Normal
Stopped
Lit/Flashing
Closed
Closed
Closed
0
0
0
0
Notified Information
PT operation status
Battery status
Screen switch strobe
Numeral setting strobe flag
Character string setting strobe flag
Printer operating status
Backlight status
Global window open status
Local window1 open status
Local window2 open status
15
13
12
11
10
7
6
5
4
3
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
Bit
Make a program which runs in the host so that leading edge of bit 12 (screen
switching strobe) in the second word (word m + 1) from the beginning of the PT
status notify area is checked.
Setting
Operation
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Summary of Contents for NT21 Series
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