82
TIMH(21) is a decrementing ON-delay timer instruction which requires an SV,
The SV is input to the thousandths of a second.
ATIM(22) is a decrementing ON-delay timer with a hardware adjustment for
the SV. On the SP16 and SP20, the hardware adjustment is the same for
both ATIM(22) and ATM1(25).
ATM1(25) and ATM2(26) are available with the SP16 and SP20 only. Like
ATIM(22), they are decrementing ON-delay timers and the SV can be set by
hardware adjustments on the front of the CPU. Unlike ATIM(22), the SV can
also be set in a word.
CNT is a decrementing counter instruction and RDM(23) is a reversible drum
counter instruction. Both require a TC number and a SV. Both are also con-
nected to multiple instruction lines which serve as an input signal(s), a reset,
and for RDM(23), an up/down input. RDM(23) also requires specification of
the first word in the results table.
CNTH(24) is a high-speed incrementing counter that is available with the
SP16 and SP20 only. It can count pulses as fast as 3.3 kHz.
Any one TC number cannot be defined twice, i.e., once it has been used as
the definer in any of the timer or counter instructions, it cannot be used
again. Once defined, TC numbers can be used as many times as required as
operands in instructions.
TC numbers run from 00 through 15. No prefix is required when using a TC
number as a definer in a timer or counter instruction. Once defined as a tim-
er, a TC number can be prefixed with TIM for use as an operand in certain
instructions. The TIM prefix is used regardless of the timer instruction that
was used to define the timer. Once defined as a counter, a TC number can
be prefixed with CNT for use as an operand in certain instructions. The CNT
is also used regardless of the counter instruction that was used to define the
counter.
TC numbers can be designated as operands that require either bit or word
data. When designated as an operand that requires bit data, the TC number
accesses a bit that functions as a ‘Completion Flag’ that indicates when the
time/count has expired, i.e., the bit, which is normally OFF, will turn ON when
the designated SV has expired. When designated as an operand that re-
quires word data, the TC number accesses a memory location that holds the
present value (PV) of the timer or counter. The PV of a timer or counter can
thus be used as an operand in CMP(32), or any other instruction for which
the TC area is allowed. This is done by designating the TC number used to
define that timer or counter to access the memory location that holds the PV.
TC numbers TC 11 through TC 15 (just TC 14 and TC 15 for the SP10) are
assigned to specific instructions, as shown in the table below.
TC number
Instruction
Applicable PCs
TC 11
ANALOG TIMER 1, ATM1(25)
SP16, SP20
TC 12
ANALOG TIMER 2, ATM2(26)
SP16, SP20
TC 13
HIGH-SPEED COUNTER, CNTH(24)
SP16, SP20
TC 14
HIGH-SPEED TIMER, TIMH(21)
SP10, SP16, SP20
TC 15
ANALOG TIMER, ATIM(22)
SP10, SP16, SP20
Note The present value of timers and counters can be monitored through the Pro-
gramming Console. Refer to the Bit/TC Monitor and Multibit/TC Monitor oper-
ations.
Instruction Set
Section 3-7