Python

Using Python to connect to a power supply

Many programing languages offer support for connecting to peripherals using RS232 or USB. This is an example script written in Python .

#!/usr/bin/env python2
# coding=utf-8
# Name:			KnielPowerSupplySocketCommEnhanced.py
# Function:		Demo
#			Starts with connect dialog (IP and port)
# 			Connects to device
#			Starts loop which asks for query commands

import socket
import sys

# detect proper input function
try:
    input = raw_input
except NameError:
    pass

# init screen
#
print(chr(27) + "[2J")
print("\033[1m" + 'Kniel Power Supply Socket Example')
print("\033[0m")

# ask user for IP & Port
#
print("Enter connection information ...")
targetIP = input("Insert IP (example: 192.168.1.1): ")
targetPORT = input("Insert Port (default: 10001): ")

# check user input
#
if not targetIP:  # empty IP is mission critical
    sys.exit("\nEmpty IP error")
if not targetPORT:
    print("Falling back to default port")
    targetPORT = "10001"  # if empty - use default port

# Try to connect to ip:port
#
srvsock = socket.socket()
srvsock.settimeout(3)  # 3 second timeout on commands
print("\nTrying to establish connection to " + targetIP + ":" + targetPORT)
targetPORT = int(targetPORT)  # Port must be integer
try:
    srvsock.connect((targetIP, targetPORT))
except socket.timeout:
    sys.exit("Socket timeout")
except socket.error:
    sys.exit("Socket error")
except Exception as e:
    print(e)
    sys.exit("Unknown error")

print("Connection established\n")

# Start user input loop
#
while True:
    n = input("Insert query or (c)ancel?: ")
    if n == "c":
        print("\nClosing socket")
        srvsock.close()
        print("\n\nBye Bye")
        break  # stops the loop
    else:
        MESSAGE = n + "\r"
        try:
            srvsock.sendall(MESSAGE)
        except TypeError:
            srvsock.sendall(MESSAGE.encode('ascii'))
        print("Send:\t\t" + MESSAGE)
        # receive
        data = srvsock.recv(4096)
        try:
            print("Received:\t" + data)
        except TypeError:
            print("Received:\t" + data.strip().decode('ascii'))