Migrating Website (& eCommerce/OpenCart) over to HTTPS – SyedTips – 9

Caution: This by no means is a step-by-step or exhaustive guide on installing SSL Certs on your website. This will simply share some notes I made yesterday while migrating my site over to HTTPS. Exercise extreme caution. I’m not responsible (in any way whatsover) for any loss or fall in rankings or loss of revenue or downtime due to application of notes. I caution because I’m not a Web expert and I don’t understand the ramifications of experimenting with this. Hence, this post is only for Educational purposes 🙂

I spent almost the whole of my new year 2017 Day 1 migrating over from http://potentiallabs.com to https://potentiallabs.com  and likewise moving our main eCommerce Store (running off OpenCart) over to https://potentiallabs.com/cart

 

SSHing into C.H.I.P in Headless Mode – SyedTips – 8

Overview:

This post will walk you through the 3 methods of SSHing into the C.H.I.P without using any external Display Screen. This is helpful if you don’t have the HDMI/VGA add on modules for the CHIP or don’t have an old TV that takes in those oldie RCA composite video signals.


After waiting for more than 6 months, the C.H.I.P finally found a place next to a Banana in my home:

img_20161206_220645
If you don’t know the relation between a Banana and CHIP, don’t worry 😛

The first thing todo when you get something is to power it on and see the funky lights that come up to make sure it’s not DoA (Dead on Arrival). And then, take a pic and Tweet it out to show off to the world 😛

Once done, now figure out how to get started with it.

It’s easier if we have the HDMI/VGA add-on module for the CHIP that’ll allow us to simply hook up the CHIP to a display unit and get started with a K/B & Mouse. I didn’t buy one, so I’m now worrying how do I get started with. Turns out, the CHIP and the PC can be directly connected to each other through a simple Micro USB Cable and tinkered with.

An extract from http://docs.getchip.com/chip.html#headless-chip that outlines these three methods:

Headless CHIP

One of the most amazing features of CHIP is that it’s insanely simple to use it as small, wireless computer. Low power requirements, battery-powered with charge management, and both WiFi and Bluetooth connectivity makes CHIP easy to run as a headless, autonomous machine. Of course, you’ll still want to access it and control it without a monitor or keyboard. You can control CHIP with another computer and a serial or network connection. Here’s how you do this.

Begin

If you want to use CHIP without a monitor or keyboard attached, there’s a few ways to do this:

  • Serial connection between a computer and CHIP with a micro-USB cable (USB OTG)
  • Serial connection between a computer and CHIP with USB to UART cable
  • Secure Shell (SSH) over wireless or wired ethernet

OK, all the info for getting started with any of the 3 methods is there in the link above. Why do we even need this post?

Except… Method 1 won’t work on my PC!

C.H.I.P doesn’t show up as a recognized COM Port on my Windows 10 PC 🙂

Unknown CDC Device. No COM Port assigned
Unknown CDC Device. No COM Port assigned

So Method 1 from the official docs won’t work for us (at least for now). Let’s move onto the 2nd Method

Method 2:

Use a USB-Serial Console/Debug cable, hook it up and SSH.

img_20161201_190932

img_20161201_191011

Now, we can simply open up Putty and enter our COM Port of the USB-Serial Cable to login into the C.H.I.Ps console:

chip_boot_2

Yay!

Now, while you’re inside, you can go and setup the CHIP to connect to your WiFi network so that you can SSH into it.

Method 3:

chip_network

Edit the interfaces file and add creds for the local WiFi:

chip_wifi_settings

You can now reboot, wait for a min and SSH into the CHIP directly through it’s IP or hostname:

chip_putty

chip_putty_inside

All good! End of Story!

Nope, Method 1 (USB – PC) didn’t work, so let’s make it work!

I found an excellent tip by lordhex on the community forums here: https://bbs.nextthing.co/t/putty-connection-step-by-step-for-windows/1636/11 and I did just that to get this method working.

I made the CHIP install itself against this driver, and boy, it finally showed up as a COM port!

chip_driver_installation   chip_driver_filechip_driver_win_10_installed

chip_driver_win_10_installed_com_port

chip_com_port_working

chip_com_port

Make sure you have disabled the Driver Install from Unknown Sources restriction on Windows 10 (to do this, hit Shift and restart PC, and you’ll find that option there).

I’ve uploaded the Driver File that I used and you can simply download and use when the CHIP shows up as a Composite device instead of showing up as a COM port.

Download from here: https://www.dropbox.com/sh/ng9acv78t0wn6mo/AACAFKRu4LNqvN5XRuFMj7Noa

Happy C.H.I.P.ping!

Recursive batch Script to get latest/static file name – SyedTips – 7

If you followed my earlier tip, notice how I always passed in Image.png as an image file into tesseract to get a text value? This is totally fine if you can source static Image files and make sure they are available at a particular location.

However, what if you’re using a live camera that saves a stream of Images? I used mjpg-streamer to live stream images on a web browser and also save them on a Raspberry Pi.

Following is the bash command that captures images from a USB WebCam and streams it over:

./mjpg_streamer -i "./input_uvc.so -r 640x480 -f 1" -o "./output_http.so -w /usr/local/www" -o "./output_file.so -f /home/pi/Camera_Output -c /usr/bin/mjpg-streamer-overwrite.sh"

The above command does the following 3 things:

  1. Stream Images over the Web/Browser
  2. Save Images to a local folder on the Raspberry Pi
  3. Invoke a custom Script

Here’s how the local folder containing the saved streamed image files looks like:

filenames_sample

Now here’s the challenge: Firstly, tesseract can only take in a defined fileName as an argument and since we’re invoking tesseract from Python, we can’t simply use a script to get the latest file name and pass it as a parameter.

So here’s what I did to solve this: Get the latest file and rename it to Image.png in that same folder. So at any instance, the latest captured image file is always Image.png. Now, simply pass this as an argument into tesseract and all’s done 🙂

I used the following code snippet to get latest file pointed as Image.png:

# move the temporary file to a given filename
cd /home/pi/syed

cp -f -T `find -type f -name '2015*' -printf "%C@\t%P\n" |sort -r -k1,1 |head -1 |cut -f 2-` /home/pi/syed/Image.png

I saved this snippet into mjpg-streamer-overwrite.sh which is being invoked on every Image capture as shown earlier.

P.S: A more detailed script that shows debug messages:

#!/bin/bash

# comment out the following line to disable messages
#VERBOSE=1

if [ $VERBOSE ]; then
  echo -e "Rename script started at:\t$(date)";
  echo -e "Parameter \$1 is:\t\t$1"
  echo -e "current directory is:\t\t$(pwd)"
  echo -e "move command is:\t\tmv -T -f \"$1\" 'Image.jpg'"
fi

# move the temporary file to a given filename
cd /home/pi/syed
cp -f -T `find -type f -name '2015*' -printf "%C@\t%P\n" |sort -r -k1,1 |head -1 |cut -f 2-` /home/pi/syed/Image.png

RES=$?
if [ $VERBOSE ]; then
  echo -e "move command returned:\t\t$RES"
fi

Thanks 🙂

Invoking Shell commands from Python – SyedTips – 6

While building an ALPR (Automatic License Plate Recognition) System on a Raspberry Pi in 2013, I came across tesseract  which is a very powerful OCR (Optical Character Recognition) tool.

Tesseract is a command line tool which means it has to be invoked as a command from the shell/terminal (and it works on both Windows and *nix):

tesseract imagename outputbase [-l lang] [-psm pagesegmode] [configfiles...]

Since my main image capture and trim script was based on Python (triggered from a WebPage), I had to find a way to invoke tesseract from within Python. At first, I looked out for python libraries and wrappers of tesseract and had a hard time getting them to run on the Raspberry Pi.

Eventually, I wondered if there was a way to invoke shell commands from Python; and yeah!

Using subprocess, you can do just that:

import subprocess
subprocess.call(["tesseract", "/home/pi/syed/Image.png", "/home/pi/OpenCV/OCR_Data"])

Pass each argument to the invoked command separated with , in “”

Thanks.

IoT project ideas and use cases – SyedTips – 5

One of my acquaintances pinged me today asking for suggestions/ideas for his Engineering project themed around IoT. At first, I gave my standard reply:

iot_suggestion

And at that instance, it hit me to get ideas from use-cases provided by leading IoT Companies such as the Kaa Project (http://www.kaaproject.org/) and many others.

I’ve compiled below a list of IoT Project Ideas for your Engineering Projects or IoT use-case demos and have listed them below with links back to the source. You can use these as a starting point and generate your own use cases or directly implement one of these. I’ll try adding in more use cases from other vendors. Happy Making (instead of ready-made buying :P). Ohh, it’s Engineer’s Day today. Happy that.

IoT Use Cases – Kaa Internet of Things platform

kaa_iot_use_cases
Source: http://www.kaaproject.org/iot-use-cases/

The following use-case examples were taken from: http://www.kaaproject.org/iot-use-cases/

 

Continue reading “IoT project ideas and use cases – SyedTips – 5”

Getting two extra pairs of VCC/GND on Arduino Uno (and others) – SyedTips – 4

We often come across projects where we’d like to quickly hook up a sensor or an actuator that works on 5V to an Arduino (Uno and others) without using a breadboard. Since the Uno has only one 5V Pin, an easy way to get additional pairs of VCC+GND is to use the ICSP headers available for the Atmega328 and Atmega16U2.

icsp_connector_pinout

img_20160911_203557_735
Orange jumper connected to VCC (5V) and Yellow to GND

Thanks.

Adding a (extra) Hardware Serial Port using I2C on Arduino or other MCU – SyedTips – 3

One cool thing/feature I learned from the Arduino Uno WiFi board was how to implement/add an extra hardware Serial Port to the existing MCU using a I2C to Serial Bridge.

The Atmega328P MCU on the Arduino Uno has only one Hardware Serial port. If we’re interfacing a Serial Device to this MCU and would also like to use Serial debugging, an option is to use SoftwareSerial (which comes with it’s own set of issues and limitations). A better option is to have an I2C – Serial Bridge that’d allow the host MCU to interface with another Serial Device.

The Arduino.org team did this splendidly and used this SC16IS750IBS to have the MCU talk with the on-board ESP8266 through this I2C to Serial Bridge.

img_20160910_232432_905

i2c_uart_pin

You can read more about the implementation and details on the product page: http://www.arduino.org/products/boards/arduino-uno-wifi

Thanks.

Combining multiple ESP bin files into 1 for production – SyedTips – 2

If you natively develop firmware on the ESP8266, you’d eventually have to flash multiple bin files to different locations on the Flash Module of ESP8266 (or on SoC itself for ESP8285).

flash_mem_allocation

In order to create a single bin file, populate the individual bin files at their respective addresses in the official Espressif Flash tool as shown below:

Flash_Tool.png

Once done, select the checkboxes of the individual files that you’d like to include and hit the Combine Bin button shown above:

That should give you a single bin file as shown below:

single_bin_file

Now, you can simply use the Flash Tool itself or esptool.py/exe to flash this single bin file at address 0x00000.

I found a simple batch file online that uses esptool.exe (for Mac/Linux, you can use esptool.py with the proper arguments) to flash bins to the ESP.

The following code goes into the batch file that calls the esptool.exe and flashes the bin file (mare sure esptool.exe and the bin file are in the same folder).

@echo off
set /p comport= Comport (example 3, 4, ..)           :

echo Using com port: %comport%

esptool.exe -vv -cd nodemcu -cb 115200 -cp COM%comport% -ca 0x00000 -cf at.bin 

pause

The above script will simply ask the user for the COM port of the USB-Serial Cable/Adapter to which an ESP (in boot-mode) is connected and flash it.

The above method can be also be used if you’re provisioning users themselves to flash/update firmware over to the ESP if FOTA is not implemented (at least that’s how I plan to use it for my ESP dev board).

Thanks.

Externally powering the DragonBoard 410C – #SyedTips – 1

I recently got access to a DragonBoard 410c and started hooking it up at 4 in the morning. After flashing the OS over to the SD Card, to my utter dismay, the DC input jack wouldn’t allow a standard DC barrel to fit in. I was furious since this barrel adapter didn’t come with the box either.

img_20160909_011728 img_20160909_011901

However, there’s always another way 🙂

Now, there’s a mini USB port, which *can* be used to power up from a 5V USB port. However, the 410C doesn’t support powering up the board through this 5V port. Here’s why it doesn’t:

usb_port_power

Notice the above section talk about using an onboard SYS_DCIN pin available on the Low Speed Expansion Connector that can be used to power the board externally.

dcin

Use any one of the SYS_DCIN and GND pin and wire it up to DC Adapter  with SYS_DCIN going to the +ve terminal. These pins are those adjacent to the Analog Expansion. Supports 6.5V to 18V.

img_20160908_050912

And the Dragon Breathes at 5 in the morning! (notice the first boot from SD Card flashing process taking place. After this, you can simply remove the SD card as the OS is now flashed onto the onboard eMMC).

img_20160908_050902

Now that we got it running, I figured out there has to be a better way to do this.

DC-DC Connector-Converter:

I got one of these this evening from a computer store and it’s marked “G”. These are usually called as Laptop Charger pin adapters and should be available at most computer/spares stores. This should now do the trick in a more aesthetic way.

img_20160909_011933 img_20160909_011951 img_20160909_012400_024

Thanks 🙂

SyedTips – Short tidbits from my knowledge and experiences

Hey Makers & Readers,

‘ve been thinking for a long time to share quick tips and tricks (and lessons learnt) from my daily experiences of being a Tinkerpreneur (aka Hacker tinkering with anything I can lay my hands on) and would use the hastag #SyedTips (Yo 😛 )

I have so much “useless” knowledge in my Brains which I’d like to dump off and recover some free space.

I’ve been inspired by my Ustaad Shaikh Yawar Baig, who through his daily short and sweet Fajr Reminders audio podcasts have shared massive knowledge, lessons and life experiences, management tips, business lessons, Entrepreneurship lessons, advice, etc etc etc which now is a coveted treasure and is easily now many thousands of podcasts hours combined.

I’ve also recently signed up for Adafruit’s daily tip newsletter (https://www.adafruitdaily.com/) and love those daily tips.

I’ll be tipping on a lot of topics and will start categorizing them as this thing grows. You’re encouraged to point out any mistakes I make and/or add in your extra tips as long as it revolves around that particular tip’s context.

I might also jump off into video tips, though that will take some time (and will feature on my YouTube channel).

Read my first #SyedTip here 🙂

Disclaimer: Most of my Tips will be from my experiences and knowledge (and may occasionally be incorrect or outdated). Please advise caution when using some of these tips and do the necessary background research/work. I take no responsibility, whatsoever for any damages/destruction arising out of my Tips. #StupidNecessaryDisclaimer