403
Special Instructions
Section 5-28
Description
PWM(––) can be used with the functions listed in the following table.
PWM(––) is used to output pulses with the specified duty factor from port 1 or
2. The output can be set to one of three frequencies: 5.9 kHz, 1.5 kHz, or 91.6
Hz. The pulse output continues until INI(61) is executed to stop it.
In order for PWM(––) to be executed, the specified port must be set for vari-
able duty factor pulse outputs in the PC Setup. Set the leftmost digit of
DM 6643 to 1 to enable variable duty factor pulse output from port 1, and set
the leftmost digit of DM 6644 to 1 to enable variable duty factor pulse output
from port 2. It is not possible to output normal pulses from a port that is set for
variable duty factor output.
Note
Refer to
1-5 Pulse Output Function
for more details.
Operand Settings
P specifies the port where the pulses will be output. Pulses are output from
port 1 when P=001, and pulses are output from port 2 when P=002.
F specifies the frequency of the pulse output, as shown in the following table.
D specifies the duty factor of the pulse output, i.e., the percentage of time that
the output is ON. D must be BCD from 0001 to 0099 (1% to 99%). The duty
factor is 75% in the following diagram.
Flags
ER:
There is an error in the operand settings.
PWM(––) is executed without a Pulse I/O Board installed.
The PC Setup is not set for variable duty factor pulse output.
PWM(––) is executed in an interrupt subroutine while a pulse I/O or
high-speed counter instruction is being executed in the main program.
Indirectly addressed EM/DM word is non-existent.
(Content of
*
EM/
*
DM word is not BCD, or the EM/DM area boundary
has been exceeded.)
5-28-14 DATA SEARCH – SRCH(––)
Unit/Board
Function
Pulse I/O Board
Pulse outputs 1 and 2
F
Frequency
000
5.9 kHz
001
1.5 kHz
002
91.6 Hz
T
t
on
=D (1% to 99%)
t
on
T
R
1
:
First word in range
IR, SR, AR, DM, EM, HR, TIM/CNT, LR
N
:
Number of words
IR, SR, AR, DM, EM, HR, TIM/CNT, LR, #
Ladder Symbols
Operand Data Areas
@SRCH(
−−
)
N
R
1
C
C
:
Comparison data, result word
IR, SR, AR, DM, EM, HR, LR
SRCH(
−−
)
N
R
1
C
