Toshiba T2N - Manual (Page 123)

2.INTERNAL OPERATIONS
110 PROSEC T2N
The timer register used in the timer instruction is updated (increased), and the
timing relay within the special relays (S0040 - S0047) is updated.
•
updating the timer register
The number of system interrupts which occur during the timer update cycle
(=scan cycle) are counted and these counts are added up in the timer register
which is started up by the timer instruction (TON, TOF, SS, TRG).
The 10msec system interrupt is used for the timer update. The timer reset and
the time up processing are performed when running the timer instruction.
timer
classification
timer register
(timer device)
preset range Notes
0.01 second
timer
T000~T063
(T.000~T.063)
0~32767
(0~327.67 seconds)
0.1 second
timer
T064~T511
(T.064~T.511)
0~32767
(0~3276.7 seconds)
on delay timer (TON)
off delay timer (TOF)
single shot timer (SS)
timer trigger (TRG)
*) Take the criteria for the time for performing the timer register update
as follows.
22µs/timer register (update time)
•
Timing relay update
The timing relay (S0040 - S0047) ON/OFF status is controlled by using the
10msec system interrupt. The binary counter is configured as shown on the
next page. (When RUN is started up, they are all OFF.)
2.4.3
Timer update
10msec system interrupt
timer timer timer
scan cycle scan cycle
timer update timer update
scan