Omron NT-series Programmable Terminal V022-E3-1 - Manual (Page 211)

Caution


  
  
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Section 5-5
6-5 Notification of the Operating Status to the PC
(Determining the NT600S Operating Status)
The status (operating statuses, etc.) of the NT600S can be determined from the
PC by reading the “PT status” word in the PT status notify area allocated in the PC
memory.
NT600S PC
PT stopped
PT status notify area
Currently displayed screen
Screen
number
Content upgrade memory table
PT status
6-5-1 Ascertainable NT600S Statuses (Notified Operating Statuses)
[“PT status notification bits” of the PT status notify area]
15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 Bit
0 0 0 0
Word
m+2
PT status notification bits 0 0 PT status
Battery
(1 (ON) = low / 0 (OFF) = normal)
Screen switch strobe flag
Numeral setting strobe flag
PT operating status
(1(ON) = operating / 0 (OFF) = stopped)
15 14 13 12 11 10 9 8 Bit
The NT600S statuses that the PC can determine are listed below.
Low voltage of battery installed in NT600S (battery: option)
NT600S operating/stopped status
Screen switches
Data input

PT operating status (bit 15)
When the NT600S is in the RUN mode this bit is set to ON (1). In other modes
and while the system menu is displayed it is OFF (0). When this bit is OFF allo-
cated bits and words cannot be read or written to.
During the run mode, ON (1) is periodically written into this bit. In order to check
whether the NT600S is operating normally or not, write OFF (0) to this bit : if it is
ON (1) 30 seconds later the NT600S is running, and if it is OFF (0), the NT600S
is stopped.
In order to ensure system safety, be sure to periodically read the PT operating
status bit at the host during operation to confirm that the PT is always operating
correctly.