Category Archives: Development

MQTT with BeagleBone and ESP8266 – MQTT on ESP8266 with temperature sensor

2017-03-23 admin

After loading the firmware into the device esp8266

MQTT with BeagleBone and ESP8266-MQTT ESP8266

we now connect this module with a DHT11 temperature and humidity sensor. Here is how we connect the sensor to the ESP module

In this example we will consider the option of putting the nodemcu in sleep. To have the node back form the sleep the system has to reboot and it is necessary to connect the PIN D0 (GPIO16) to RST PIN as specified in the nodemcu documentation

Nodemcu sleep

Let us take a look at the lua code; It consists of init.lua and tempumid.lua files.

We analyze now the main points of each file

init.lua

-- init.lua
SSID="SSDNAME" -- SSID 
PASSWORD="passwordssid" -- SSID password
TIMEOUT=10000    -- timeout to check the network status
EXSENSOR1="tempumid.lua"    -- module to run
MQTTSERVER="mqttbrokeraddress"   -- mqtt broker address
MQTTPORT="1883"  -- mqtt borker port
MQTTQOS="0" -- qos used

-- Set the netowrk parameters and get ip address
wifi.setmode(wifi.STATION)
wifi.sta.config(SSID, PASSWORD)
wifi.sta.getip()

-- Check the network status after the TIMEOUT interval
tmr.alarm(0, TIMEOUT,tmr.ALARM_SINGLE, function()
    status=wifi.sta.status()
    
    -- if esp8266 got the ip
   if (status == wifi.STA_GOTIP ) then

       dofile(EXSENSOR1)
        
    
    else
        -- Without ip restart the node
        print("Error acquiring ip address=",status)
        node.restart()
    end


end

-- init.lua

SSID="SSDNAME" -- SSID

PASSWORD="passwordssid" -- SSID password

TIMEOUT=10000 -- timeout to check the network status

EXSENSOR1="tempumid.lua" -- module to run

MQTTSERVER="mqttbrokeraddress" -- mqtt broker address

MQTTPORT="1883" -- mqtt borker port

MQTTQOS="0" -- qos used

-- Set the netowrk parameters and get ip address

wifi.setmode(wifi.STATION)

wifi.sta.config(SSID, PASSWORD)

wifi.sta.getip()

-- Check the network status after the TIMEOUT interval

tmr.alarm(0, TIMEOUT,tmr.ALARM_SINGLE, function()

status=wifi.sta.status()

-- if esp8266 got the ip

if (status == wifi.STA_GOTIP ) then

dofile(EXSENSOR1)

else

-- Without ip restart the node

print("Error acquiring ip address=",status)

node.restart()

end

In the file we set the the parameters to access the wifi network, the address and port of the MQTT broker and the file to be run on the ESP after wifi connection to the access point is estabilished. If the ESP does’t acquire the netowrk address the system is restarted.

tempumid.lua

-- tempumid.lua
CNAME="room1" -- Client name 
AMBIENT="home"  -- Ambient name
TTOPIC     = AMBIENT.."/"..CNAME.."/temperature"  -- Temperature topic
HTOPIC     = AMBIENT.."/"..CNAME.."/humidity"  -- Humidity topic 
STOPIC     = AMBIENT.."/"..CNAME.."/status"  -- Status topic
CTOPIC     = AMBIENT.."/"..CNAME.."/command" --Command topic   
MTOPIC     = AMBIENT.."/"..CNAME.."/monitor" --Monitor topic


sleep_in_seconds= nil --Sleep in seconds


TUPDATE = 15 -- Time interval for update monitor in seconds
TUPTEMP = 10 -- Time interval for update temperature and humidity values
SPIN         = 4  -- Sensor pin
TGEN = 5 -- Time interval in seconds usend in various trm


-- Define Client Name and connection parameters
mqt = mqtt.Client(CNAME, 60, "", "", 1) 

-- Subscribe to the topics and send status to the status topic
mqt:on("connect", function() 
    mqt:subscribe(STOPIC, MQTTQOS)
    mqt:subscribe(CTOPIC, MQTTQOS)
    mqt:subscribe(MTOPIC, MQTTQOS)
    mqt:subscribe(TTOPIC, MQTTQOS)
    mqt:subscribe(HTOPIC, MQTTQOS)
    send_status("Sensor ready again")
end )

-- Callback when mqtt is offline
mqt:on("offline", function() print("mqtt offline");  end)

--Callback to manage messages 
mqt:on("message", function(client, topic, data) 
    manage_message(client, topic, data) 
end)


-- Function to filter the messages
function manage_message(client, topic, data) 
    -- If CTOPIC: command topic
    if topic == CTOPIC then
        --print("Command")
        -- If the command is Restart
        if data == "Restart" then
            send_status("Restarting")
            send_mstatus("Restarting")
            tmr.alarm(2, TGEN*1000, tmr.ALARM_SINGLE, node.restart)
            --print("restart")
        -- If the command is null    
        elseif data == nil then
           -- print("Command not valid")
            send_status("Command not valid")
        
        
        else
            -- Check the Sleep command           
            i=string.len(data)
            dato=string.sub(data,1,5)
          
            if dato == "Sleep" then
                ndato=string.sub(data,6)
                TSLEEP=tonumber(ndato)
                if TSLEEP ~= nil then
                    if TSLEEP >= 1 then
                        -- Sets the interval in seconds to sleep
                        sleep_in_seconds=TSLEEP*60
                        esp_sleep()
                    else
                        -- Send an error in Sleep command
                        send_status("Sleep command error")
                    
                    end
                else
                    -- Send an error in Sleep command 
                    send_status("Sleep command error")
                end

            else
                -- Command not managed           
                send_status("Command not valid")      

            end
            
        end
        
    end
end

-- Function to send messages to STOPIC: status topic
function send_status(message)
    mqt:publish(STOPIC, message, MQTTQOS, 0)
    
end

-- Fucntion to send messages to MTOPIC: monitor topic
function send_mstatus(message)
    mqt:publish(MTOPIC, message, MQTTQOS, 0)
    
end

-- Function to display temp and hum
function display_temphum(temp,humi)
    print("Temperature=%d, Humidity=%d",temp,humi)
end

 
-- Function to read and publish temperature and humidity
function read_temp_hum(client)
    status, temp, humi, temp_dec, humi_dec = dht.read(SPIN)
    if status == dht.OK then
    
        mqt:publish(TTOPIC, temp,MQTTQOS, 0)
        mqt:publish(HTOPIC, humi, MQTTQOS, 0)
        
       -- display_temphum(temp,humi)
       
    elseif status == dht.ERROR_CHECKSUM then
        print( "DHT Checksum error." )
    elseif status == dht.ERROR_TIMEOUT then
        print( "DHT timed out." )
    end
end


-- Function that sleeps esp8266
function esp_sleep()
 
    send_status("Sensor going to sleep now")
    send_mstatus("Sensor going to sleep now")
    -- Delayd sleep to send the message above.
    tmr.alarm(3, TGEN*1000, tmr.ALARM_SINGLE, function() 
        node.dsleep(sleep_in_seconds*1000000) 
    end)
end

-- Connection to the mqtt server at the mqttport
mqt:connect(MQTTSERVER, MQTTPORT, 0, 1)

--Sends periodically the temperature and humidity to the topics
tmr.alarm(1, TUPTEMP*1000, tmr.ALARM_AUTO, function() read_temp_hum(mqt) end)

-- Sends periodically a message to the monitor topic
tmr.alarm(4, TUPDATE*1000, tmr.ALARM_AUTO, function() send_mstatus("Sensor Ready") end)

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-- tempumid.lua

CNAME="room1" -- Client name

AMBIENT="home" -- Ambient name

TTOPIC = AMBIENT.."/"..CNAME.."/temperature" -- Temperature topic

HTOPIC = AMBIENT.."/"..CNAME.."/humidity" -- Humidity topic

STOPIC = AMBIENT.."/"..CNAME.."/status" -- Status topic

CTOPIC = AMBIENT.."/"..CNAME.."/command" --Command topic

MTOPIC = AMBIENT.."/"..CNAME.."/monitor" --Monitor topic

sleep_in_seconds= nil --Sleep in seconds

TUPDATE = 15 -- Time interval for update monitor in seconds

TUPTEMP = 10 -- Time interval for update temperature and humidity values

SPIN = 4 -- Sensor pin

TGEN = 5 -- Time interval in seconds usend in various trm

-- Define Client Name and connection parameters

mqt = mqtt.Client(CNAME, 60, "", "", 1)

-- Subscribe to the topics and send status to the status topic

mqt:on("connect", function()

mqt:subscribe(STOPIC, MQTTQOS)

mqt:subscribe(CTOPIC, MQTTQOS)

mqt:subscribe(MTOPIC, MQTTQOS)

mqt:subscribe(TTOPIC, MQTTQOS)

mqt:subscribe(HTOPIC, MQTTQOS)

send_status("Sensor ready again")

end )

-- Callback when mqtt is offline

mqt:on("offline", function() print("mqtt offline"); end)

--Callback to manage messages

mqt:on("message", function(client, topic, data)

manage_message(client, topic, data)

end)

-- Function to filter the messages

function manage_message(client, topic, data)

-- If CTOPIC: command topic

if topic == CTOPIC then

--print("Command")

-- If the command is Restart

if data == "Restart" then

send_status("Restarting")

send_mstatus("Restarting")

tmr.alarm(2, TGEN*1000, tmr.ALARM_SINGLE, node.restart)

--print("restart")

-- If the command is null

elseif data == nil then

-- print("Command not valid")

send_status("Command not valid")

else

-- Check the Sleep command

i=string.len(data)

dato=string.sub(data,1,5)

if dato == "Sleep" then

ndato=string.sub(data,6)

TSLEEP=tonumber(ndato)

if TSLEEP ~= nil then

if TSLEEP >= 1 then

-- Sets the interval in seconds to sleep

sleep_in_seconds=TSLEEP*60

esp_sleep()

else

-- Send an error in Sleep command

send_status("Sleep command error")

end

else

-- Send an error in Sleep command

send_status("Sleep command error")

end

else

-- Command not managed

send_status("Command not valid")

end

-- Function to send messages to STOPIC: status topic

function send_status(message)

mqt:publish(STOPIC, message, MQTTQOS, 0)

end

-- Fucntion to send messages to MTOPIC: monitor topic

function send_mstatus(message)

mqt:publish(MTOPIC, message, MQTTQOS, 0)

end

-- Function to display temp and hum

function display_temphum(temp,humi)

print("Temperature=%d, Humidity=%d",temp,humi)

end

-- Function to read and publish temperature and humidity

function read_temp_hum(client)

status, temp, humi, temp_dec, humi_dec = dht.read(SPIN)

if status == dht.OK then

mqt:publish(TTOPIC, temp,MQTTQOS, 0)

mqt:publish(HTOPIC, humi, MQTTQOS, 0)

-- display_temphum(temp,humi)

elseif status == dht.ERROR_CHECKSUM then

print( "DHT Checksum error." )

elseif status == dht.ERROR_TIMEOUT then

print( "DHT timed out." )

end

-- Function that sleeps esp8266

function esp_sleep()

send_status("Sensor going to sleep now")

send_mstatus("Sensor going to sleep now")

-- Delayd sleep to send the message above.

tmr.alarm(3, TGEN*1000, tmr.ALARM_SINGLE, function()

node.dsleep(sleep_in_seconds*1000000)

end)

end

-- Connection to the mqtt server at the mqttport

mqt:connect(MQTTSERVER, MQTTPORT, 0, 1)

--Sends periodically the temperature and humidity to the topics

tmr.alarm(1, TUPTEMP*1000, tmr.ALARM_AUTO, function() read_temp_hum(mqt) end)

-- Sends periodically a message to the monitor topic

tmr.alarm(4, TUPDATE*1000, tmr.ALARM_AUTO, function() send_mstatus("Sensor Ready") end)

The temumid.lua file manages the measurement of temperature and humidity, the subscription on MQTT broker with submission of the data. Global parameters have been set to manage the topic, the waiting time in tmr.alarm. There are in particular the following topics

/home/room1/temperature: measured temperature topic.
/home/room1/humidity: measured humidity topic.
/home/room1/status : Status topic. The status is sent at the start and at request from the command topic /home/room1/command.
/home/room1/monitor: Status of the esp sent periodically to this topic.
/home/room1/command: Other clients can send commands to the esp:
- Restart: Restarts the esp.
- Sleep n: Put to sleep for n seconds the esp.

There are various service functions to manage all. The comments in the code describe each feature.

In the next article we will set up the esp with the relay

MQTT with BeagleBone and ESP8266 – MQTT on ESP8266 with Relay

Development, Software

C Eclipse project reading temperature and humidity on Beaglebone

2017-02-15 admin

After the cross building and DHT11 sensor setup on Beaglebone Black

Remote debug on Beaglebone

Sensors on Beaglebone

Temperature and humidity reading on Beaglebone in python

now we show how to create a C project , using the C source code available with the Adafruit library

Adafruit Python DHT Sensor Library

Using Eclipse, we create a project for the reading of our sensor. It calls the functions in the C code of the Adafruit library. These sources are imported into the Eclipse project

and using the sample C code dhtSensor.c, which contains the main C program, we read the sensors by calling the funtions available in Adafruit C sources; the usage is similar to what seen in Python.

Running

./dhtSensor

1	./dhtSensor

it shows the help instructions

root@beaglebone:~/examples# ./dhtSensor
Usage:  sudo ./dhtSensor [11|22|2302] GPIOpin#
Example: sudo ./dhtSensor 11 P8_11 - Read from a DHT11 sensor connected to P8_11 Pin
root@beaglebone:~/examples#

root@beaglebone:~/examples# ./dhtSensor

Usage: sudo ./dhtSensor [11|22|2302] GPIOpin#

Example: sudo ./dhtSensor 11 P8_11 - Read from a DHT11 sensor connected to P8_11 Pin

root@beaglebone:~/examples#

To read the DHT11 sensor on pin P8_11 we have to run

./dhtSensor 11 P8_11

1	./dhtSensor 11 P8_11

The output is the following

Here is the Eclipse C project

dhtSensor Eclipse project

Development, Software

DHT11 sensor reading on BeagleBone with node.js

2017-02-06 admin

In the previous article we read the temperature and humidity from DHT11 sensor in python

Temperature and humidity reading on Beaglebone in python

We perform now the same operation in javascript. We download the dht module for node.js. The module is available on the website

beaglebone dht

Log on BeagleBone in ssh as debian (temppwd as password) and run

sudo npm install -g mocha
sudo npm install -g chai
sudo npm install -g beaglebone-dht@0.0.3
sudo npm install -g beaglebone-dht --save

sudo npm install -g mocha

sudo npm install -g chai

sudo npm install -g beaglebone-dht@0.0.3

sudo npm install -g beaglebone-dht --save

to install the module globally.

For the sensor reading create a file test.js with the following code inside

var dht = require('/usr/local/lib/node_modules/beaglebone-dht'),
    sensor = dht.sensor('DHT11');
var i=0;

do {
        read=dht.read('P8_11');
        try {

                valore=read['humidity'];
                if(valore<=100.00&&valore>=0.0)  {

                        console.log(read);
                        break;
                        }
                }
        catch(err)  {
                        console.log("Error in sensor reading!");

                 }

        sleep(2000);

} while (i<15)

function sleep(milliseconds) {
  var start = new Date().getTime();
  for (var i = 0; i < 1e7; i++) {
    if ((new Date().getTime() - start) > milliseconds){
      break;
    }
  }
}

var dht = require('/usr/local/lib/node_modules/beaglebone-dht'),

sensor = dht.sensor('DHT11');

var i=0;

do {

read=dht.read('P8_11');

try {

valore=read['humidity'];

if(valore<=100.00&&valore>=0.0) {

console.log(read);

break;

}

catch(err) {

console.log("Error in sensor reading!");

}

sleep(2000);

} while (i<15)

function sleep(milliseconds) {

var start = new Date().getTime();

for (var i = 0; i < 1e7; i++) {

if ((new Date().getTime() - start) > milliseconds){

break;

}

Reading is performed running

sudo node test.js

1	sudo node test.js

The result in our case is the following

The same code can be run from Cloud9 IDE. Access the IDE on BeagleBone with the link http: //beaglebone.local:3000 and create a file named dht.js with the following code inside

var b = require('bonescript');
var dht = require('/usr/local/lib/node_modules/beaglebone-dht'),
    sensor = dht.sensor('DHT11');

var i=0;

do {
        read=dht.read('P8_11');
        try {

                valore=read['humidity'];
                if(valore<=100.00&&valore>=0.0)  {

                        console.log(read);
                        break;
                        }
                }
        catch(err)  {
                        console.log("Error in sensor reading!");

                 }

        sleep(2000);

} while (i<15)

function sleep(milliseconds) {
  var start = new Date().getTime();
  for (var i = 0; i < 1e7; i++) {
    if ((new Date().getTime() - start) > milliseconds){
      break;
    }
  }
}

var b = require('bonescript');

var dht = require('/usr/local/lib/node_modules/beaglebone-dht'),

sensor = dht.sensor('DHT11');

var i=0;

do {

read=dht.read('P8_11');

try {

valore=read['humidity'];

if(valore<=100.00&&valore>=0.0) {

console.log(read);

break;

}

catch(err) {

console.log("Error in sensor reading!");

}

sleep(2000);

} while (i<15)

function sleep(milliseconds) {

var start = new Date().getTime();

for (var i = 0; i < 1e7; i++) {

if ((new Date().getTime() - start) > milliseconds){

break;

}

The script execution gives the following result

Here is the link to download the two sample files

Node.js sample

Cloud9 sample

Development, Software

Temperature and humidity reading on Beaglebone in python

2017-02-02 admin

In the previous article we connected the DHT11 sensor to the Beaglebone

Sensors on Beaglebone

We install at this point the library in python and modules in c to read the sensor. The site with documentation about the library is

Adafruit Python DHT Sensor Library

mkdir temperature
cd temperature
git clone https://github.com/adafruit/Adafruit_Python_DHT.git

mkdir temperature

cd temperature

git clone https://github.com/adafruit/Adafruit_Python_DHT.git

Install the prerequisites

apt-get update
apt-get install build-essential python-dev

1 2	apt-get update apt-get install build-essential python-dev

Proceed to the installation of the library with the python command

cd Adafruit_Python
python setup.py install

1 2	cd Adafruit_Python python setup.py install

Enter the examples directory and do the following for reading the sensor values (dht 11 and pin P8_11)

cd examples
 ./AdafruitDHT.py 11 P8_11

1 2	cd examples ./AdafruitDHT.py 11 P8_11

The result in this case is the following

Development, Software

Sensors on Beaglebone

2017-02-02 admin

After describing the Beaglebone and its development tools

Startup of the Beaglebone development board

Development tools on Beaglebone

as an example we show how to interact with the Beaglebone and a temperature and humidity sensor.

Among the most popular we finde the DHT11 sensor. The sensor has 4 pin; we have to connnect it to the power supply through a resistance of 4.7 or 10 kΩ. In our case we have a three-pin DHT11 sensor with the resistance already included in the circuit. In the case of the only sensor follow as specified in the following article

DHT humidity sensor

The following image shows the connections with Beaglebone

In the article Development tools on Beaglebone we showed the Beaglebone headers; in this case we used 3.3V, ground and P8_11 headers.

In the next article we will install a library in python and modules in C to read temperature and humidity

Temperature and humidity reading on Beaglebone in python

Development, Software

Remote debug on Beaglebone

2017-01-25 admin

In the previous article we have prepared the environment with Eclipse for cross building for BeagleBone

Cross building for Beaglebone

Now we shall configure Eclipse and BeagleBone to debug the code directly on BeagleBone.

On BeagleBone install gdbserver

sudo apt-get install gdbserver

1	sudo apt-get install gdbserver

On the Debian system with Eclipse install gdb-multiarch

sudo apt-get install gdb-multiarch

1	sudo apt-get install gdb-multiarch

From Eclipse access to Run-> Debug Configurations

Double-click C++ Remote Application to set parameters

At the next window, create a new ssh connection with the New button

Enter the parameters for the connection

Set the remote destination folder for the file and execution management; with the browse button choose where to copy the files, and with the field “Commands to execute before application” will give execute permissions to the file

In our case we create a folder esempi under /root on the BeagleBone where to debug remotely

Set the multarch debugger in the Debugger Tab and other startup parameters and gdb command line settings

Set the port of the remote debug server installed on BeagleBone in the Gdbserver Settings Tab

Create .gdbinit files in the project folder with the command

To start debugging run the configuration we set

Eclipse connects with BeagleBone and performs remote debugging opening the Debug Perspective

Development, Software

Cross building for Beaglebone

2017-01-19 admin

In the article on the Debian environment we prepared the linux machine for the development of embedded systems

Debian development envinronment

In the article on building an image for the Orange PI PC we installed the cross build tools for armhf environment

Building Armbian for Orange PI PC

Starting from the clean image of the Debian envinronment we list the steps required to install the cross compiling environment. We log on Debian Desktop as sviluppo/ password.

As a preliminary step we install the cross toolchains in Debian

https://wiki.debian.org/CrossToolchains

Create the file crosstools.list in the /etc/apt/sources.list.d folder

sudo vi /etc/apt/sources.list.d/crosstools.list

1	sudo vi /etc/apt/sources.list.d/crosstools.list

and add the line

deb http://emdebian.org/tools/debian/ jessie main

1	deb http://emdebian.org/tools/debian/ jessie main

Save the file and add the key of the repository embedian.org

sudo apt-get install curl

1	sudo apt-get install curl

curl http://emdebian.org/tools/debian/emdebian-toolchain-archive.key | sudo apt-key add -

1	curl http://emdebian.org/tools/debian/emdebian-toolchain-archive.key \| sudo apt-key add -

Install the following packages and add the armhf architecture

sudo dpkg --add-architecture armhf
sudo apt-get update
sudo apt-get install crossbuild-essential-armhf

sudo dpkg --add-architecture armhf

sudo apt-get update

sudo apt-get install crossbuild-essential-armhf

We install at this point the Eclipse IDE for Cpp downloading the IDE for Linux 64bit

Eclipse IDE

Unzip the eclipse package under / home /sviluppo.

Install the jre java

sudo vi /etc/apt/sources.list

1	sudo vi /etc/apt/sources.list

Add the line at the end of the file

# Backport Testing on stable
# JDK 8
deb http://ftp.de.debian.org/debian jessie-backports main

# Backport Testing on stable

# JDK 8

deb http://ftp.de.debian.org/debian jessie-backports main

Run the following commands

sudo apt-get update
sudo apt-get install openjdk-8-jre

1 2	sudo apt-get update sudo apt-get install openjdk-8-jre

Run Eclipse from the eclipse folder to start the IDE

As a first example we create a simple program in C for BeagleBone.

Create a new project in C, by inserting the following data

Select both configurations

Enter the cross compiler prefix and path

Press Finish.
Add to the project a source file in C

Insert the following simple code

#include <stdio.h>

int main()
   {
   printf("Hello, world.\n");
   return 0;
   }

#include <stdio.h>

int main()

{

printf("Hello, world.\n");

return 0;

}

Proceed with the build by selecting the project with the right mouse button and choosing Build Project

Transfer the generated files on BeagleBone. You can use scp or ftp.

Give execution permissions to the file and run it

chmod +x samplec
./samplec

1 2	chmod +x samplec ./samplec

The result is of course the text inserted in the code

Development, Software

Development tools on Beaglebone

2017-01-11 admin

In the previous article we have installed and updated to the latest Debian image our BeagleBone

Debian sd card setup for Beaglebone Black

We also enabled the network services to access the board using the hostname.

After these changes we can access the Beaglebone using the following address in the the browser

http: //beaglebone.local

The web interface presents several examples of code executed with bonescript, javascript library based on node.js framework

Node.js

You can perform these simple examples to begin to interact with the board. There are also links to the development tools such as Cloud9, Nodered and informations about these development tools

Clicking on Cloud9 we access at the section dedicated to this tool. It is shown how to create a simple example and to run at boot the code placing it into the autorun folder in the IDE interface. From this section we can access to the Cloud9 ide available on port 3000 of the Beaglebone site

For more information about the tool, refer to the site

Cloud9

Accessing to the Nodered section we find the link to the web page about the basic informations about Nodered

Getting stared with Nodered

and the link to the Nodered ide, running at 1880 port of the web server running on BeagleBone

Beaglebone Nodered

In the web page about the first steps for Nodered there are examples with which to start using the tool. From the web site https://nodered.org we can have more informations about the tool.

In addition to tools in javascript on BeagleBone there are C/C++ compilers, Python interpreter and the possibility to add additional development tools.

From the home page of the our BeagleBone board web interface, http: //beaglebone.local, we find the informations about all available headers and functions. The following image shows the expansion headers

In next articles we will show some code examples with the development board.

Development, Software

Openelec addon building for Orange PI PC

2016-12-18 admin

In the article about the OpenELEC build for Orange PI PC

Openelec building for Orange PI PC

we created the environment and compiled the OpenELEC image for our development board. We integrate what it has been said in the previous article showing how to build the Openelec addons for our Orange PI PC board.

As stated in the linked article we have to open a shell command window in the OPENELEC-OPIPC folder

cd OPENELEC-OPIPC

1	cd OPENELEC-OPIPC

Using the graphical interface in Debian we can verify the availabilty of the official addons structure. To add the unofficial ones we have to run from the OpenELEC-OPIPC folder

git clone https://github.com/jernejsk/unofficial-addons.git  packages/addons/unofficial

1	git clone https://github.com/jernejsk/unofficial-addons.git packages/addons/unofficial

Now we proceed to build an official addon and an unofficial one. The packages that you can build ara available in the official folder as shown below

and in the unofficial folder

We build the official pvr.iptvsimple addon with the command

PROJECT=H3 ARCH=arm scripts/create_addon pvr.iptvsimple

1	PROJECT=H3 ARCH=arm scripts/create_addon pvr.iptvsimple

For the unofficial we build the p7zip module

PROJECT=H3 ARCH=arm scripts/create_addon p7zip

1	PROJECT=H3 ARCH=arm scripts/create_addon p7zip

The compiled addons are availablein the following folder

/home/sviluppo/orangepi/openelec/OPENELEC-OPIPC/target/addons/7.0/H3/arm/

1	/home/sviluppo/orangepi/openelec/OPENELEC-OPIPC/target/addons/7.0/H3/arm/

In the case of errors in the compliation check the logs and proceed consequently. For example in the case of trasmission the system was not able to download the source package using the link in the package.mk file

/home/sviluppo/orangepi/openelec/OPENELEC-OPIPC/packages/addons/unofficial/addons/service/downloadmanager/transmission/package.mk

1	/home/sviluppo/orangepi/openelec/OPENELEC-OPIPC/packages/addons/unofficial/addons/service/downloadmanager/transmission/package.mk

To overcome this unexpected error we added another link to the package, i.e. we changed the package.mk file from

PKG_URL="http://download.transmissionbt.com/files/$PKG_NAME-$PKG_VERSION.tar.xz"
PKG_DEPENDS_TARGET="toolchain zlib libressl curl libevent"

1 2	PKG_URL="http://download.transmissionbt.com/files/$PKG_NAME-$PKG_VERSION.tar.xz" PKG_DEPENDS_TARGET="toolchain zlib libressl curl libevent"

PKG_URL="http://download.transmissionbt.com/files/$PKG_NAME-$PKG_VERSION.tar.xz"
PKG_URL="https://github.com/transmission/transmission-releases/raw/master/$PKG_NAME-$PKG_VERSION.tar.xz"
PKG_DEPENDS_TARGET="toolchain zlib libressl curl libevent"

PKG_URL="http://download.transmissionbt.com/files/$PKG_NAME-$PKG_VERSION.tar.xz"

PKG_URL="https://github.com/transmission/transmission-releases/raw/master/$PKG_NAME-$PKG_VERSION.tar.xz"

PKG_DEPENDS_TARGET="toolchain zlib libressl curl libevent"

In this way, the transmission addon has been compiled correctly, always with the command

PROJECT=H3 ARCH=arm scripts/create_addon transmission

1	PROJECT=H3 ARCH=arm scripts/create_addon transmission

Development, Software

Nodemcu Enduser_setup module lua sample(part2)

2016-11-28 admin

After the firmware build and its upload to the nodemcu dev kit, we connected a switch to pin D5, as shown in the previous article

Nodemcu Enduser_setup module lua sample(part1)

We finally can upload some sample code in which we use the enduser_setup module

Open ESPlorer and load the following sample code

webserver.lua

-- webserver.lua
--webserver sample from the nodemcu github
if srv~=nil then
 srv:close()
end

gpio.mode(1, gpio.OUTPUT)
srv=net.createServer(net.TCP)
srv:listen(80,function(conn)
    conn:on("receive", function(client,request)
        local buf = ""
        local _, _, method, path, vars = string.find(request, "([A-Z]+) (.+)?(.+) HTTP")
        if(method == nil)then
            _, _, method, path = string.find(request, "([A-Z]+) (.+) HTTP")
        end
        local _GET = {}
        if (vars ~= nil)then
            for k, v in string.gmatch(vars, "(%w+)=(%w+)&*") do
                _GET[k] = v
            end
        end
        buf = buf.."<h1> Hello, NodeMcu.</h1><form src=\"/\">Turn PIN1 <select name=\"pin\" onchange=\"form.submit()\">"
        local _on,_off = "",""
        if(_GET.pin == "ON")then
              _on = " selected=true"
              gpio.write(1, gpio.HIGH)
        elseif(_GET.pin == "OFF")then
              _off = " selected=\"true\""
              gpio.write(1, gpio.LOW)
        end
        buf = buf.."<option".._on..">ON</opton><option".._off..">OFF</option></select></form>"
        client:send(buf)
    end)
    conn:on("sent", function (c) c:close() end)
end)

-- webserver.lua

--webserver sample from the nodemcu github

if srv~=nil then

srv:close()

end

gpio.mode(1, gpio.OUTPUT)

srv=net.createServer(net.TCP)

srv:listen(80,function(conn)

conn:on("receive", function(client,request)

local buf = ""

local _, _, method, path, vars = string.find(request, "([A-Z]+) (.+)?(.+) HTTP")

if(method == nil)then

_, _, method, path = string.find(request, "([A-Z]+) (.+) HTTP")

end

local _GET = {}

if (vars ~= nil)then

for k, v in string.gmatch(vars, "(%w+)=(%w+)&*") do

_GET[k] = v

end

buf = buf.."<h1> Hello, NodeMcu.</h1><form src=\"/\">Turn PIN1 <select name=\"pin\" onchange=\"form.submit()\">"

local _on,_off = "",""

if(_GET.pin == "ON")then

_on = " selected=true"

gpio.write(1, gpio.HIGH)

elseif(_GET.pin == "OFF")then

_off = " selected=\"true\""

gpio.write(1, gpio.LOW)

end

buf = buf.."<option".._on..">ON</opton><option".._off..">OFF</option></select></form>"

client:send(buf)

end)

conn:on("sent", function (c) c:close() end)

end)

riasserawifi.lua

--riazzerawifi.lua
-- Starts the portal to choose the wi-fi router to which we have
-- to associate
wifi.sta.disconnect()
wifi.setmode(wifi.STATIONAP)
--ESP SSID generated wiht its chipid
wifi.ap.config({ssid="Mynode-"..node.chipid()
, auth=wifi.OPEN})
enduser_setup.manual(true)
enduser_setup.start(
  function()
    print("Connected to wifi as:" .. wifi.sta.getip())
  end,
  function(err, str)
    print("enduser_setup: Err #" .. err .. ": " .. str)
  end
);

--riazzerawifi.lua

-- Starts the portal to choose the wi-fi router to which we have

-- to associate

wifi.sta.disconnect()

wifi.setmode(wifi.STATIONAP)

--ESP SSID generated wiht its chipid

wifi.ap.config({ssid="Mynode-"..node.chipid()

, auth=wifi.OPEN})

enduser_setup.manual(true)

enduser_setup.start(

function()

print("Connected to wifi as:" .. wifi.sta.getip())

end,

function(err, str)

print("enduser_setup: Err #" .. err .. ": " .. str)

end

);

init.lua

-- init.lua
--Access Point management
pin = 5 --Input PIN
Resetta=0   --Variable used to manage AP reset
gpio.mode(pin,gpio.INPUT)   --Pin 5 in input mode

--If pin input is High let's start the nodemcu portal
if (gpio.read(pin)==gpio.HIGH ) then 

    Resetta=1
end

-- Check if reset the AP credential
if Resetta==1 then 

    -- Start the nodemcu portal
    tmr.alarm(0, 5000, 0, function() dofile("riazzerawifi.lua") end)

else
    -- Start the webserver wiht ip defined by Wi-Fi router
    tmr.alarm(0, 5000, 0, function() dofile("webserver.lua") end)

end

-- init.lua

--Access Point management

pin = 5 --Input PIN

Resetta=0 --Variable used to manage AP reset

gpio.mode(pin,gpio.INPUT) --Pin 5 in input mode

--If pin input is High let's start the nodemcu portal

if (gpio.read(pin)==gpio.HIGH ) then

Resetta=1

end

-- Check if reset the AP credential

if Resetta==1 then

-- Start the nodemcu portal

tmr.alarm(0, 5000, 0, function() dofile("riazzerawifi.lua") end)

else

-- Start the webserver wiht ip defined by Wi-Fi router

tmr.alarm(0, 5000, 0, function() dofile("webserver.lua") end)

end

It is possible to download the above samples at the following link

Sample code

Here is the documentation about the enduser_setup module

enduser_setup module documentation

The example consists of three files:

init.lua: It is executed at the startup of the esp8266.
riazzerawifi.lua: It starts the portal to connect and save the configuration to your Access Point.
webserver.lua: It starts the webserver sample on the nodemcu.

As you can see from the code in init.lua, when the pin D5 is in the state HIGH, we start the portal using enduser_setup module. In the case in which the pin D5 is in the state LOW the esp8266 acquires the IP from an Access Point defined previously after which the test webserver starts.

To save the access point confguration to which we want to connect we place the switch in order to have the HIGH input on pin D5 and reboot the card.

From a PC we can observe the presence of another access point, defined in the file riazzerawifi.lua

wifi.ap.config({ssid="Mynode-"..node.chipid()
, auth=wifi.OPEN})

1 2	wifi.ap.config({ssid="Mynode-"..node.chipid() , auth=wifi.OPEN})

composed by Mynode string + ChipID module

We can connect to this access point and via browser we access to the portal at the ip address 192.168.4.1

Select or enter the SSID of an access point providing the correct password. After the connection reposition the switch to have the LOW state for pin D5 and reboot the nodemcu dev kit.

Now the system will automatically connect to the SSID defined previously and starts the example of the web server.

Please refer to the Lua documentation nodemcu for further study and usable modules

LUA Nodemcu Documentation

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