Python Library for Industrial Shields Raspberry PLCs

Summary

This library is developed for Industrial shields Raspberry PLCs and is only supported by Python3. It performs the following functions:

• Analog Read
• Analog write
• Digital Read
• Digital write
• Relay

Installation

To install this library, You need to first clone this repository to your PLC using the following command:

$git clone -b <tagname> https://github.com/Industrial-Shields/rpiplc-python3-lib

tagname = v1.X.X = RPI PLC Version 3

tagname = v2.X.X = RPI PLC Version 4

You can find the available tags here: https://github.com/Industrial-Shields/rpiplc-python3-lib/tags

After which, run the following command to install the library:

$python3 setup.py install

Once installed, make sure to comment the following lines from config.txt file:

You can find the file here:

/boot/config.txt

Reboot the PLC once done.

#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 outpust, 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("I0.2")

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("I0.0")

digital_write()

rpiplc.digital_write("Q0.0",rpiplc.HIGH)

relay()

rpiplc.digital_write("R0.1",rpiplc.HIGH)

Examples

from rpiplc_lib import rpiplc

def digital_read_write():
    rpiplc.pin_mode("I0.0",rpiplc.INPUT)
    read_value=rpiplc.digital_read("I0.0")
    print("The I0.0 is reading: {}".format(read_value))
 
    rpiplc.pin_mode("Q0.0",rpiplc.OUTPUT)
    rpiplc.digital_write("Q0.0",rpiplc.HIGH)
    rpiplc.delay(1000)
    rpiplc.digital_write("Q0.0",rpiplc.LOW)
    rpiplc.delay(1000)
    
    
def analog_read_write():
    rpiplc.pin_mode("I0.2",rpiplc.INPUT)
    read_value=rpiplc.analog_read("I0.2") # 0 - 2047
    print("The I0.2 is reading: {}".format(read_value))

    rpiplc.pin_mode("A0.0",rpiplc.OUTPUT)  	
    rpiplc.analog_write("A0.0",1024) # 2.5v Output
    rpiplc.delay(2000)
    rpiplc.analog_write("A0.0",4095) # 10v Output
    rpiplc.delay(2000)
    rpiplc.analog_write("A0.0",0)


def relay_test():
    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:
        digital_read_write()
        analog_read_write()
        relay_test()


if __name__ == "__main__":
    main()