Introduction
In this short blog post, we will see how to install and use the Python library for Industrial Shields' Raspberry PLCs. The library can be found here.
Installation
Github link
To install this library, you need to first clone this repository to your PLC using the following command:
# For RPi PLC v3
$ git clone -b v1.0.0 https://github.com/Industrial-Shields/python3-librpiplc/
# For RPi PLC v4
$ git clone -b v2.0.0 https://github.com/Industrial-Shields/python3-librpiplc/
After which, run the following command to install the library:
$python3 setup.py install
#dtoverlay=mcp23017,noints,mcp23008,addr=0x20
#dtoverlay=mcp23017,noints,mcp23008,addr=0x21
#dtoverlay=i2c-pwm-pca9685a,addr=0x40
#dtoverlay=i2c-pwm-pca9685a,addr=0x41
#dtoverlay=ads1015,addr=0x48
#dtparam=cha_enable=true,cha_gain=1
#dtparam=chb_enable=true,chb_gain=1
#dtparam=chc_enable=true,chc_gain=1
#dtparam=chd_enable=true,chd_gain=
#dtoverlay=ads1015,addr=0x49
#dtparam=cha_enable=true,cha_gain=1
#dtparam=chb_enable=true,chb_gain=1
#dtparam=chc_enable=true,chc_gain=1
#dtparam=chd_enable=true,chd_gain=1
#dtoverlay=ads1015,addr=0x4a
#dtparam=cha_enable=true,cha_gain=1
#dtparam=chb_enable=true,chb_gain=1
#dtparam=chc_enable=true,chc_gain=1
#dtparam=chd_enable=true,chd_gain=1
#dtoverlay=ads1015,addr=0x4b
#dtparam=cha_enable=true,cha_gain=1
#dtparam=chb_enable=true,chb_gain=1
#dtparam=chc_enable=true,chc_gain=1
#dtparam=chd_enable=true,chd_gain=1
API
PLC Initialization
rpiplc.init("RPIPLC_57R")
You can choose from the below model list to fill the parameter.
PLC Model list
- RPIPLC_19R
- RPIPLC_21
- RPIPLC_38AR
- RPIPLC_38R
- RPIPLC_42
- RPIPLC_50RRA
- RPIPLC_53ARR
- RPIPLC_54ARA
- RPIPLC_57AAR
- RPIPLC_57R
- RPIPLC_58
Pin initialization: It is a good practice to initialize the pins as inputs or outputs. For this, use the following code:
pin_mode(pin_name,mode) #mode can be rpiplc.OUTPUT; rpiplc.INPUT or 1;0
Pin Functions
analog_read():
rpiplc.analog_read("A0.0")
analog_write():
rpiplc.analog_write("A0.0",value) #Here the value is in the range of 0 to 4095. 0 being 0V and 4095 is 10v
digital_read():
rpiplc.digital_read("Q0.0")digital_write():
rpiplc.digital_write("Q0.0",rpiplc.HIGH)relay():
rpiplc.digital_write("R0.1",rpiplc.HIGH)Example Code
from rpiplc_lib import rpiplc
def digitalreadwrite():
rpiplc.pin_mode("Q0.0",1)
rpiplc.digital_write("Q0.0",rpiplc.HIGH)
rpiplc.delay(1000)
rpiplc.digital_write("Q0.0",rpiplc.LOW)
rpiplc.delay(1000)
def analogreadwrite():
rpiplc.pin_mode("A1.0",rpiplc.INPUT)
read_value=rpiplc.analog_read("A1.0")
print("The A1.0 is reading : ",read_value)
rpiplc.pin_mode("A1.1",rpiplc.OUTPUT)
rpiplc.analog_write("A1.1",1024) # 2.5v Output
rpiplc.delay(2000)
rpiplc.analog_write("A1.1",4095) # 10v Output
rpiplc.delay(2000)
rpiplc.analog_write("A1.1",0)
def relaytest():
rpiplc.pin_mode("R0.1",rpiplc.OUTPUT)
rpiplc.digital_write("R0.1",rpiplc.HIGH)
rpiplc.delay(1000)
rpiplc.digital_write("R0.1",rpiplc.LOW)
rpiplc.delay(1000)
def main():
rpiplc.init("RPIPLC_57R")
while True:
digitalreadwrite()
analogreadwrite()
relaytest()
if __name__ == "__main__":
main()
Other relevant links
Raspberry PLC
InfluxDB and Raspberry PLC
Python library for Raspberry PLC