Try debugging Python on Raspberry Pi with Visual Studio.

So that you can make Python as easily as possible

Both Raspberry Pi and Python have just started, and it's quite tough. So, I tried it from the earnest desire to debug Python on Visual Studio. Somehow, I feel like I can go. I don't think the hurdles for preparing the environment are high, so why not give it a try?

Target

I want to reduce the loop of modifying with Sakura Editor, transferring with WinSCP, and executing Python from Tera Term.

A simple one with low functionality is good.

I want to avoid things that are no longer needed once I get used to Python.

Countermeasure plan

It seems that Python will also work with Visual Studio. It seems that you can also do your favorite "step execution".

Examination of countermeasures

I couldn't consider multiple plans because I don't have much knowledge of Python, but I want to move it because "step execution" is hard to throw away on the subject of strengthening debugging. In order to run it on Visual Studio, it cannot be run on Win10 because it cannot be compiled (it is unknown whether the expression is appropriate).

** I can't compile because I don't have a library. If you don't have it, you have to make it. ** **

Library creation plan

Win10 does not have GPIO, so if you make a temporary GPIO library, can you execute it without a compile error? We will respond with the strategy. RPI. I use GPIO, but I am not particular about it. For now, it's just the most familiar choice.

environment

Windows10 64bit home VisualStudio 2019 Community Python C# Python 3.7 .NET 4.7.2 psycopg2 2.8.6 Npgsql v4.1.5 PostgreSQL PostgreSQL 13.0 64-bit A5:SQL Mk-2 2.15.1

What to make this time

GPIO library RPI. Make GPIO with a dummy. Create a Windows Forms program in C # for operation. RPI. PostgreSQL is used for communication between GPIO and C #. This is because it is troublesome to use interprocess communication, and the DB is more useful for this usage in terms of logs. You can play with it as you like in SQL. Python is psicopg2 and C # is Npgskl to connect to the DB.

** Simulate I / O using SQL with GPIO library and C #. ** **

Creating a PostgreSQL DB

I created a DB called pizero and created two tables. inputtable is for input, from C # to GPIO library. outputtable is for output, from GPIO library to C #.

create database pizero;

create table outputTable(
id serial
,hiduke timestamp
,pin integer
,data integer
,memo varchar(20)
);

create table inputTable(
id serial
,hiduke timestamp
,pin integer
,data integer
,memo varchar(20)
);

Creating a Python project

Select Python. If you can't find it, you need to install it. It's done. Open Python Package Management. Enter psycopg2. The one with the up arrow seems to be an update, so I think it should be updated. It has been various. At the beginning, click Run the following command. Click Promote Now. It's done. It has been added to the list. Make a Python sauce. There is an error in import.

piTes1.py

import time
import RPi.GPIO as GPIO

PIN_IN = 2
PIN_OUT =3
PIN_OUT2 =4

GPIO.setwarnings(False)

print('start')

GPIO.setmode( GPIO.BCM )
GPIO.setup( PIN_IN, GPIO.IN )
GPIO.setup( PIN_OUT, GPIO.OUT )
GPIO.setup( PIN_OUT2, GPIO.OUT )

for i in range(3):
    inData = GPIO.input( PIN_IN )

    if( inData == GPIO.LOW ):
        print('PIN_OUT')
        GPIO.output( PIN_OUT, GPIO.HIGH )
        GPIO.output( PIN_OUT2, GPIO.LOW )
    else:
        print('PIN_OUT2')
        GPIO.output( PIN_OUT, GPIO.LOW )
        GPIO.output( PIN_OUT2, GPIO.HIGH )

GPIO.cleanup()

print('end')

Add a new item. Make a Python package. The name is important. It's done. Also add a new item. I will add it in the package I made earlier. I want to put it in a package. Create an empty Python file. The name is important. It has been added to the list. Create the source of GPIO library. The connection information to the DB needs to be adjusted to the environment. Server: localhost Port: 5432 Database: pizero User: postgres Password: postgres

GPIO.py

import time
import psycopg2

BCM = 1

IN = 1
OUT = 2

LOW = 0
HIGH = 1

outCount = 0
inCount = 0

connection = psycopg2.connect("host=localhost port=5432 dbname=pizero user=postgres password=postgres")
connection.autocommit = True

def setwarnings(flg):
	return 0

def setmode(mode):
	global outCount
	global inCount

	cur = connection.cursor()
	cur.execute("select coalesce(max(id),0) from outputtable")
	row = cur.fetchone()

	outCount = row[0]

	cur.execute("select coalesce(max(id),0) from inputtable")
	row = cur.fetchone()

	inCount = row[0]

	cur.close()

	return 0

def setup(pin,type):
	return 0

def cleanup():
	connection.close()
	return 0

def input(pin):
	global inCount

	ret = 0
	rowcount = 0

	while rowcount == 0:

		strSQL = "select * from inputtable where id > " + str(inCount)
		cur = connection.cursor()
		cur.execute(strSQL)
		row = cur.fetchone()

		rowcount = cur.rowcount

		if rowcount == 0:
			print('wait')
			time.sleep(5.0)

		if rowcount > 0:
			print(row)
			inCount = row[0]
			ret = row[3]

		cur.close()

	return ret

def output(pin,data):
	global outCount

	strSQL = "insert into outputtable(hiduke, pin, data, memo) values (now(), " + str(pin) + ", " + str(data) + ", 'output')"
	cur = connection.cursor()
	cur.execute(strSQL)
	cur.close()

	outCount += 1

	return 0

It just defines the functions used by the GPIO library. SQL processing for communication is included in the input function and output function. input function Wait endlessly for inserts from C #. Data larger than the known id is regarded as new data. I'll wait, but I'll get only one. output function Insert to inform C #. I'll just let you know, so don't wait.

There is no error in import. I'm happy.

C # project creation

Make it with Windows Forms. It's done. NuGet. Select the reference and search for Npgskl. Install it. It has been added to the reference settings. Make a form. The C # source has been compiled.

Form1.cs

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;

using Npgsql;

namespace piTes1CS
{
    public partial class Form1 : Form
    {
        string connString = "Server=localhost;Port=5432;User Id=postgres;Password=postgres;Database=pizero";
        NpgsqlConnection conn;

        int inCount = 0;
        int outCount = 0;

        public Form1()
        {
            InitializeComponent();
        }

        private void Form1_Load(object sender, EventArgs e)
        {
            inCount = 0;
            outCount = 0;

            conn = new NpgsqlConnection(connString);
            conn.Open();

            var strSQL = "select coalesce(max(id),0) maxid from inputtable";
            var command = new NpgsqlCommand(strSQL, conn);

            var dataReader = command.ExecuteReader();
            if (dataReader.HasRows)
            {
                dataReader.Read();
                inCount = (int)dataReader["maxid"];
            }
            dataReader.Close();

            strSQL = "select coalesce(max(id),0) maxid from outputtable";
            command = new NpgsqlCommand(strSQL, conn);

            dataReader = command.ExecuteReader();
            if (dataReader.HasRows)
            {
                dataReader.Read();
                outCount = (int)dataReader["maxid"];
            }
            dataReader.Close();
        }

        private void Form1_FormClosed(object sender, FormClosedEventArgs e)
        {
            conn.Close();
        }

        private void btnRead_Click(object sender, EventArgs e)
        {
            this.txtGPIO3.BackColor = Color.White;
            this.txtGPIO4.BackColor = Color.White;

            var strSQL = "select * from outputtable where id > " + outCount;
            var command = new NpgsqlCommand(strSQL, conn);

            var dataReader = command.ExecuteReader();
            if (dataReader.HasRows)
            {
                dataReader.Read();
                outCount = (int)dataReader["id"];
                int pin = (int)dataReader["pin"];
                int data = (int)dataReader["data"];
                string memo = (string)dataReader["memo"];

                Console.WriteLine("outCount=" + outCount + " inCount=" + inCount);

                if (pin == 3)
                {
                    this.txtGPIO3.Text = data.ToString();
                    this.txtGPIO3.BackColor = Color.Yellow;
                }
                if (pin == 4)
                {
                    this.txtGPIO4.Text = data.ToString();
                    this.txtGPIO4.BackColor = Color.Yellow;
                }
            }
            else
            {
                Console.WriteLine("wait");
            }
            dataReader.Close();
        }

        private void btnGPIO2_Click(object sender, EventArgs e)
        {
            if (this.txtGPIO2.TextLength > 0)
            {
                var strSQL = "insert into inputtable(hiduke, pin, data, memo) values (now(), 2, " + this.txtGPIO2.Text + ", 'btnWriteGPIO2')";

                var command = new NpgsqlCommand(strSQL, conn);
                command.ExecuteNonQuery();

                inCount++;
            }
        }
    }
}

C # does the opposite of Python. Insert the data for the input function of the GPIO library with the submit button. Get one data for output function of GPIO library with the receive button. The value is displayed on GPIO3 or GPIO4 with the receive button.

Try to move

To clean the table, use Truncate. It also initializes the id value.

truncate table inputtable RESTART IDENTITY;
truncate table outputtable RESTART IDENTITY;

Launch two Visual Studios and run Python and C # respectively. I started Python. I started C #. Since Python is waiting for the input function, GPIO2 is assigned to GPIO. I just set HIGH and pressed the send button. It seems that Python is working fine. After Python has executed the output function twice, press the receive button. GPIO3 is GPIO. It is displayed as LOW. Press the receive button again. GPIO4 is GPIO. It was displayed as HIGH. It seems to be working fine. It is the state of the DB after it is finished.

Try to move

** By creating a dummy of GPIO library, you can debug on Win10 instead of on RaspberryPi. ** ** Considering the function on the C # side this time, I feel that it is enough to execute it while modifying SQL. ** It's not a simulator, it's a test code, so you have to make something that matches the movement of Python **, but if you still find it easy, it's probably worth a try. It is a sensor system, and if you get the log on the actual machine and put it in the table, you may be able to try the same movement as the actual machine. You can step through and check the values of variables that are running. Even CORE i5 10 years ago is not an enemy of the zero series, it is comfortable.

I tried L Chika in the zero series just because of the IoT atmosphere. Next is. .. ..

Currently, there are two strong enemies on the breadboard. It's a gyro sensor module and a motor driver IC, but what will happen? Even though there are fewer parts than the unstable multivibrator L Chika.

The more I read a software book, the more I can do, but why is that system (electronic circuit) useless (unhelpful)?

** For handicraft level electronic work challengers, the GPIO connector is the Away. ** **

I have to focus on the strong opponents on the breadboard of Away, so I don't have much power to avoid Python. Because it is a level that can not explain the operation of the unstable multivibrator.