Timer Areas - Omron CJ2 CPU UNIT SOFTWARE User Manual

6 I/O Memory Areas

6-16 Timer Areas

Up to 4,096 timers with timer numbers T0 to T4095 can be used. There are two timer data areas: the
Timer Completion Flag Area and the Timer Present Value (PV) Area.
• Timer Completion Flags (T)
Timer numbers are used to access Completion Flags. A Completion Flag is turned ON when the set
time of the timer elapses.
• Timer PVs (T)
Timer numbers are also used to read and write the present values of timers (16-bit words). The PV
increases or decreases as the timer operates.
When a timer number is used in an operand that requires bit data, the timer number accesses the Com-
pletion Flag. When a timer number is used in an operand that requires word data, the timer number
accesses the PV.
The same timer numbers are used by all of the following instructions: HUNDRED-MS TIMER
(TIM/TIMX(550)), TEN-MS TIMER (TIMH(015)/TIMHX(551)), ONE-MS TIMER
(TMHH(540)/TMHHX(552)), TENTH-MS TIMER (TIMU(541)/TIMUX(556)), HUNDREDTH-MS TIMER
(TMUH(544)/TMUHX(557)), ACCUMULATIVE TIMER (TTIM(087)/TTIMX(555)), TIMER WAIT
(TIMW(813)/TIMWX(816)), and HIGH-SPEED TIMER WAIT (TMHW(815)/TMHWX(817)).
Precautions for Correct Use Precautions for Correct Use
It is not recommended to use the same timer number in two timer instructions because the tim-
ers will not operate correctly if they are timing simultaneously. (If two or more timer instructions
use the same timer number, an error will be generated during the program check, but the timers
will operate as long as the instructions are not executed in the same cycle.)
6-32 CJ2 CPU Unit Software User's Manual