Omron CQM1H - 08-2005, Руководство по эксплуатации

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109
Terminal Usage
Output terminal 1 Connect analog output for output 1.
Output terminal 2 Connect analog output for output 2.
2-1-1 Functions of Setting Pins
The setting pins are used to prohibit negative voltage output.
Setting pin
Status
Left Right
1 2 3
Left Right
1 2 3
JT1 Word n: Normal setting
(factory set) Word n: Negative voltage
output prohibited
JT2 Word n + 1: Normal setting
(factory set)
Word n + 1: Negative voltage
output prohibited
When negative voltage output is prohibited, 0 V is output from the voltage output
terminal if the Analog Output Unit has negative voltage output data.
Note 1. At the time of program debugging with an external device connected to the
Analog Output Unit, set the setting pins to prohibit negative voltage output
so that the wrong output will not damage the external device. Do not use the
Analog Output Unit to output negative voltage while the setting pins are set
to prohibit negative voltage output.
2. If an input circuit incorporating a pull-up resistor is connected to the Analog
Output Unit, set the setting pins to normal setting. If the setting pins are set to
prohibit negative voltage output, the Analog Output Unit will be influenced
by the synch current and no output will be ON properly.
3. Do not touch any internal components other than the setting pins.
2-2 Functions
2-2-1 Output Characteristics
The Analog Output Unit converts data from the CPU into voltage or current and
outputs the data to the voltage terminal or current terminal.
Voltage Output Data between 0000 and 07FF (hexadecimal) for output from the CPU are con-
verted into a voltage of 0 to 10 V and output.
Negative voltage is converted to 2’s complement with the MSB. Data between
F800 to FFFF (hexadecimal) for output from the CPU is converted into a voltage
of –10 to 0V and output. If negative voltage output is prohibited, 0 V will be out-
put.
Bits 11 to 14 of output data have nothing to do with output voltage. For example,
0 V is output for 0000 and 7800 (hexadecimal).
15 10 9 8 7 6 5 4 3 2 1 0
MSB LSB
These four bits have nothing to do with the output voltage.
MSB: Most significant bit
LSB: Least significant bit
Terminals
Functions
Section 2-2