Etcher – A tool to flash an SD card for the Raspberry Pi

May 12, 2017

We came across a tool called Etcher from Resin.io.  It is a tool meant to flash an image onto an SD card. This is especially useful to quickly setup your new Raspberry Pi. It is a one step process where you can select the image and flash the SD card for your project.

We put together a video that shows how to flash an image for your Raspberry Pi:

 


Raspberry Pi Zero Enclosure – 3D print time lapse!

May 7, 2017

I wanted to document my projects in vivid detail. Recently, I 3D-printed an enclosure for the Raspberry Pi Zero W. I recorded the printing process. The enclosure consists of two halves. The top piece broke while trying to remove it off the bed. In my second attempt, I printed the top piece separately and managed to remove it carefully.

Psst: I am learning to make good videos and I look forward to hearing your feedback


Jaguarboard – Yet another (not so impressive) SBC

December 29, 2015

I usually back Kickstarter projects(in the DIY electronics domain) that peek my interest. I recently backed the Pine A64, UP and the Latte Panda boards but the Jaguarboard is not one of them.

I usually look for a cool feature that would enable me to build a cool project using the backer reward. For e.g. The Latte Panda comes with onboard Wi-Fi/Bluetooth. It has an ATmega32U4 microcontroller that enables easier interface of sensors.

The Jaguarboard failed to impress me for a couple of reasons:

  1. Lack of sufficient GPIO count – They provide access to only 4 GPIO pins. I usually make use of more than 4 GPIO pins in my projects. However, it does come with an I²C port which could be used to expand the GPIO capabilities.
  2. Incompatible with the Raspberry Pi/Arduino add-on boards – It is not possible to port Raspberry Pi/Arduino projects that makes use of an add-on board to the JaguarBoard platform. It also doesn’t make sense developing expansion modules for the JaguarBoard as the lack of a broad user base is a distinct possibility.
  3. Comparison of specs on the campaign page – The campaign creators have compared the specifications of the board to the Raspberry Pi Model 1 rather than Model 2. The Raspberry Pi Model 2 comes with 1 GB RAM while Model 1 comes with 512 MB RAM. I think that is not a fair comparison.
  4. Unrealistic campaign schedule – In my opinion, the promised delivery date of the board is a tad unrealistic. They promised to deliver the boards by January 2016. The Kickstarter campaign itself ends only on January 22, 2016. As far as I know, Kickstarter takes at least 10 days to transfer the campaign money to your pocket. This puts the campaign roughly in the first week of February. Unless the campaign creators, plan to ship the boards using money out of their pocket, this is not possible.

They also have not released any planned timeline of the project. This is possible only if they already have a stash of boards manufactured, packed and stored in a warehouse.

In summary, I am not impressed by the JaguarBoard Kickstarter campaign.

 


The S.F. Bay Area is not a haven for the electronics hobbyist!

November 29, 2015

Note: This post is not a hate fest!

I realized this when I was at the Orange County Microcenter in SoCal to get my hands on the Raspberry Pi Zero.

Yep, you read that right! I had to drive 392 miles to get a $5 Raspberry Pi Zero! I plan to share the details of my trip in a later post. While I did this trip for fun, it is quite difficult to buy some discrete components in the Bay Area.

Chicago v.s. S.F. Bay Area

Chicago

I lived in the Chicago suburbs for 2 years and 3 months before I moved to the Bay Area in May/June 2014.  While living in Chicago, I had several options to buy discrete electronic components:

  • Microcenter– (2 stores in Chicago!) – Carries a lot of DIY kits (I am not talking about the Arduino and Raspberry Pi). Open Sundays.
  • American Science and Surplus (Milwaukee/Foster Ave neighborhood) – This store sells stepper motors, cool DIY science kits, test tubes, conical flasks etc. Open Sundays.
  • Chicago Electronics Distributors (Winnetka)- A distributor of Adafruit products. This guy is awesome. He used to let me arrange a late evening local pickup for emergencies.  I do not recall buying anything on a Sunday from this guy.
  • Fry’s electronics (Downer’s Grove) – The Chicago store is somewhat far away from the city. Open Sundays.
  • Radio Shack – This is no longer an option but Radio Shack carries a couple of components.

Given these options, I could always find a part locally (unless my requirement is very specific/exotic).

Hackerspaces:

There are 3 hackerspaces in the Chicago area. Pumping Station 1, Workshop 88 and the South Side hackerspace. I was a member of Pumping Station 1. It was so easy to build your own enclosures using a laser cutter. Pumping Station 1 is easily accessible from different parts of the city and the starving hacker membership was approximately $40 a month.

S.F. Bay Area:

  • Radio Shack – This is no longer an option. Radio Shack has gotten rid of a part its DIY electronics shelf. Now you could buy some basic accessories like solder.
  • Fry’s electronics – Open Sundays. You could buy some discrete resistors, capacitors etc. Arduino kits etc are ridiculously expensive.
  • Jameco – They have  a store front in Belmont. They are open only Mondays to Fridays, 9 a.m. to 5 p.m.. It is best to order your stuff online and pick it up. They sell a variety of discrete components, kits etc. They do have an online chat support to discuss your order. Good luck driving from San Francisco to Belmont in rush hour traffic.
  • oddWires – This store also allows local pick up but only on week days. I have never used this store as it is very far away from where I live.
  • Hobby engineering – This store provides pickup on all days of the week upon prior arrangement. Their store collection is not so extensive and I never had the chance to use their business.
  • Evil Mad Scientist (Sunnyvale CA) – A re-seller of Adafruit products and they also carry a lot of DIY electronics kits.  The pickup option is available only on week days during business hours.
  • Al Lasher’s Electronics – This store is open 8:30 a.m. to 5:00 p.m. on all week days and 8:30 a.m. to 2 p.m. on Saturdays.  They are a distributor of Sparkfun and they do sell a vast variety of components that peeked my interest.

 

20151128_122025

A sign inside Al Lasher’s electronics

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Al Lasher’s electronics, Berkeley CA

Craigslist!!!

If you have plenty of time in your hands and if you are trying to buy an Arduino or a Raspberry Pi, you can try crawling through craigslist. If you are lucky, there might be some one in your area who is trying to getting rid of their electronics stash.

Arduino_Raspberry Pi

Search results for arduino in the SF Bay Area Craigslist

Update (06/21/2017): A reader left a note in the comments about HSC (Halted Electronics) and Anchor Electronics in San Jose. I have been to Halted Electronics in San Jose. It is a big store and they carry an array of components but you have to be patient going through different aisles. If you are looking for cheap DC motors, HSC is a great resource. I haven’t been to Anchor Electronics. Thanks Travis!

Hackerspaces

I learned of 2 hackerspaces in the Bay Area namely Noisebridge and Tech Shop that is equipped with tools like a laser cutter. While TechShop is a bit pricey, applying for Noisebridge’s membership is a tad complicated.  You need two members who could potentially support your membership application. This is probably to prevent abuse of the hackerspace equipment. Given my socialization skills,  securing a membership is next to impossible.  I decided to navigate this situation by getting my own 3D printer.

It might appear that the Bay Area has several options for a hobbyist. It is just difficult getting to these places when they are open.

As you may have noticed, most of these places are open only on week days except for the hackerspaces. The traffic in the Bay Area is insane until around 7 p.m. (more like 7:30 ish). Most of these stores are closed for business by 7 p.m..

When I was at the Orange County Microcenter to buy the Raspberry Pi Zero, I recalled all the options I had back in Chicago.  I was told that there used to be a Micro Center in the Bay Area but they had to shut down.

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Fully stocked aisles at the Micro Center

The Bay Area is home to a lot of semiconductor manufacturers, smart device manufacturers etc. Yet, you have to go online to buy parts for your project.

As the title states, the S.F. Bay Area is not a haven for the electronics hobbyist.

P.S.: If you know of a great resource that I missed here, leave a comment.


DIY IoT Project | Planning a trip to the Sierras using a Raspberry Pi | Part 1 | DIY with Pi

June 1, 2015

Re-blogging my own post from another blog on using a Raspberry Pi to retrieve California state highway road conditions.

Mono Lake, California

DIY IoT Project | Planning a trip to the Sierras using a Raspberry Pi | Part 1 | DIY with Pi.


Travel tip: A tip to set up your Raspberry Pi in your motel room | DIY with Pi

May 24, 2015

Reblogging my own post from another site: I am traveling this memorial day weekend and I wrote a post on setting up your Raspberry Pi in a motel room to verify something quickly for a presentation etc.

Travel tip: A tip to set up your Raspberry Pi in your motel room | DIY with Pi.


Currency exchange ticker using Raspberry Pi + Pi Lite

July 8, 2013

I recently bought a Pi Lite board from Ciseco PLC, UK. The Pi Lite is an add-on hardware board for the Raspberry Pi. It comes with 126 LEDs and is controlled by an Atmega328p microcontroller (The one used in the Arduino Uno platform). The Pi-Lite uses the BCM chipset’s serial port for its communication to the Raspberry Pi.

Image

Pi Lite + Raspberry Pi inside an enclosure from Nudatech

Since the Pi Lite is a stackable add-on hardware, they have provided access to the Pi’s GPIO pins on the add-on board. It is possible to scroll messages on the Pi-Lite display by sending messages via the serial port on the Raspberry Pi. A simple step-by-step guide to setup the serial port to transmit messages to the Pi-Lite is available here.

I was able to run a simple program that fetches the currency exchange rate from the web and scroll the same on the Pi-Lite Display in two simple steps.

I got started by fetching currency exchange rate data:


import requests
import json

data = requests.get('http://rate-exchange.appspot.com/currency?from=USD&to=INR')
jsondata = json.loads(data.content)
retrieved_data = jsondata['rate']
print(retrieved_data)

We can scroll the retrieved data on the display by simply opening the serial port (The port at which the Pi-Lite is connected) and writing the string to it.


baud = 9600
port = '/dev/ttyAMA0'

ser = serial.Serial(port,baud)
ser.timeout = 0
ser.flushInput()

ser.write(str(retrieved_data))

Combining the above two steps, we have:


import requests
import json
import serial
from time import sleep

baud = 9600
port = '/dev/ttyAMA0'

ser = serial.Serial(port,baud)
ser.timeout = 0
ser.flushInput()

while True:
 data = requests.get('http://rate-exchange.appspot.com/currency?from=USD&to=INR')
 jsondata = json.loads(data.content)
 retrieved_data = jsondata['rate']
 print(retrieved_data)
 ser.write(str(retrieved_data))
 sleep(10)

I was not able to take a good picture due to the brightness of the LEDs. Hence, I am sharing a black and white video of the currency exchange rate being updated every 10 seconds:

Note: I am not promoting the Pi-Lite board!