Startup Grind 2015

Startup Grind 2015

Startup Grind 2015 was in Redwood City this February. This is my first Startup Grind. Thanks to the organizers for the scholarship. I attended the event without paying a penny!

The two day event had 1:1 sessions, panels and workshop with an incredible line of speakers.

My background is hardware so I was specifically interested in Matt Rogers and Eric Migicovosky. Matt shared his experience at Apple and how it shaped some of the decisions at Nest, how his role is evolving from the early days of Nest to a grown up Nest. Eric’s session was more into Pebble’s take on Apple watch. I loved it how cool he was in answering those questions.

I also attended the sessions with Matt Miller of Sequoia Capital, Paul from Alta Venture, Manu Kumar from K9 venture, AngelList syndicate session, Health session with Halle Taco, Jeff of Priceline, Google Venture, Mike from Instagram and Biz Stone from Twitter.

My top 3 lessons from the Startup Grind 2015.

  1. Hardware products take 2X more money and 3X more time than you think you need – Matt Rogers, Nest.
  2. Nail it before you scale it – Matt Miller of Sequoia Capital on scaling your startup.
  3. Always value people not organization – Biz Stone, Twitter co-founder.

Zuckenberg’s Year of Books: Recap of ‘The Better Angels of Our Nature’

Originally published at my medium blog.

Okay, so I just finished reading ‘The Better Angels of our Nature’ by Steven Pinker; the 2nd book of Zuckenberg’s ‘A Year of Book’ club. And here is a quick recap. If you haven’t seen my notes on the 1st book, you can check it out here.

In this book, Steven argues that violence has decreased over time. The writer discusses how violence was exercised in different times of the civilization. He argues that violence has reduced and explains why. The book starts with a vivid depiction of atrocities described in the Hebrew Bible, so detailed that I felt like ‘okay I understand, what’s next?’ But as I kept going, it became more and more appealing; opening new doors of historical, sociological and political paradigm in front of me.

Without further ado, here is my quick summary

  1. The religious brutality described in the Hebrew and Christian Bible, though fictitious, represents the thought process of the people of that time. But sensibilities toward violence have changed so much that religious people have compartmentalize their religious ideology. Their school of belief have rarely changed but their action is thoroughly tolerant and nonviolent. The writer calls it ‘a benevolent hypocrisy’.
  2. How did we get the name of our favorite drink ‘Bloody Mary’? The writer says that the name originated as the Queen Mary I of England burned 300 religious dissenters.
  3. Honor exist because everyone thinks that everyone else thinks it exists. [1]
  4. U.S. had higher homicide rate than other similar countries. Although U.S. can’t be thought of one single country, rather a collection of countries as the societal and cultural norm varies. The northern U.S. states has lower homicide rate than the southern U.S. states.
  5. War follows the power law distribution. That means it has a non-negligible probability of extreme outcome.
  6. But why war follows power law distribution? Because leaders keep increasing the atrocities of the war as time pass. As they have already spent much resource in the war, they want to avoid any chance of losing by increasing atrocity. This eventually causes wars to follow the power law distribution. [2]
  7. Many small wars cause more deaths than one fatal war.
  8. Probability of death from Boston to LA flight is same as 12 mile drive. [3]
  9. Predatory violence happens when suffering of the victim is very insignificant compared to the joy of the killer
  10. Institutional violence happens because of the societal and political rule.
  11. Will more women in power reduce violence? Yes.
  12. Women are the less violent sex of human species. Although, in any society, thought process of women are strongly correlated to their male counterparts.
  13. So what can we do to reduce violence? Increase ‘empathy’. Empathy has been a recent buzz but the writer believes that empathy alone is not a significant component for violence reduction. Empathy can hinder fairness and that in turn can cause violence.
  14. Self-control, promoting intelligence (as intelligent people believe in positive sum game), better government, people familiar with each other and women empowerment are some of the critical components towards a less violent world.
  15. Yamaguchi, the only survivor of the world’s two nuclear attack said that “The only people who should be allowed to govern countries with nuclear weapons are mothers, those who are still breast-feeding their babies”.

[1] Next time you wonder ‘what people will think’, remember this line.
[2] The same reason why we finish watching a bad movie if we have already paid for the ticket.
[3] After 9–11, an increasing number of people started travelling by road instead of air causing more travel related death than before.


Zuckenberg’s Year of Books : Reviewing ‘The End of Power’

Originally published at my Medium blog.

As part of Mark Zuckenberg’s 2015 challenge — reading a book in every two weeks, I just finished reading the 1st book — The End of Power by Moisés Naím. With numerous examples from history, politics, religion, culture and technology; the book discusses how power is decaying over time. It was a great read adding to my political & cultural knowledge base.

So I decided to note down my thoughts and some of the interesting points from the book. Without further ado, here is a quick review.

  • Powerful people are feeling more and more powerless.
  • Power itself is decreasing for various reasons — increase in the World’s population, access to education and resources are to name a few.
  • As we lack power to solve bigger problems, we focus on short term achievements. [1]
  • Power is expressed through the 4 channels — muscle, code (religious or societal norm), pitch and reward.
  • According to William Domhoff, American life was controlled by the owners and top managers of large corporations.
  • Number of autocratic countries are decreasing, even autocrats are not that much autocratic these days.
  • In the election process, one party getting absolute majority is becoming rarer.
  • Power in corporations is also reducing. In the United States, CEO turnover was higher in the 1990s than in the two previous decades. For example, Paolo Scaroni, the CEO of the Italian oil giant ENI said “When I look back at how the leaders of the main oil companies of the 1960s, 1970s or 1980s used to make decisions and run their businesses, I am amazed at the freedom and autonomy they enjoyed. From where I sit, it’s obvious that nowadays any oil company CEO has far less power than those who came before us.”
  • The term ‘dark pools’ is quite interesting. It refers to a group of institutions that seek to trade anonymously to avoid revealing their strategies. The Securities and Exchange Commission estimated that the number of active dark pools in the US market shot up from ten in 2002 to more than thirty in 2012.

My Thoughts:

The book’s message — power is decaying over time is pretty intuitive in the era of Apps and Kickstarter. In fact I personally know someone who was expressing the same opinion without even knowing about this book!

Take for example crowdfunding. I know at least 4 writers who got funded by Kickstarter and were able to publish the books. Without crowdfunding, they wouldn’t have seen the light of the day.

In my opinion, power hasn’t really gone, but the means of power is probably a more complex mix of muscle, code, pitch and reward than before.

[1] This is the most astounding thought from the book that I will remember forever. And yes, it is so true. Why you think everyone is building an App when we spend 10 hours in weekly commute to work? Why can’t people solve real problems? Because solving real problems takes longer time, more resources and a huge number of people to trust and follow your leadership. You don’t have time because you want to be a billionaire by 30. You don’t have enough resources because resources are distributed among many people. And you don’t have a huge trusted follower base as everyone is building their own app!


Hand Assembling SMD Circuit Boards

At litehouse.io, we recently got our 1st prototype board. We decided to do hand assembly of the SMD circuit board instead of sending it to the fab!

This is my 1st circuit board assembly. Soldering the SMD components can be really daunting. But if you have proper tools and resources in hand, it is not all that bad.

Here is how our soldering area looks like


Soldering in progress …


Without further ado, lets list down the necessary tools and resources used to complete the hand assembly of the SMD circuit board.

X-Tronic Hot Air Rework & Soldering Station: This (or any other brand you like) is a keeper. The kit is a collection of a bunch of necessary tools that you will need. So instead of ordering them separately, you can save $$$ on this package.

Solder tip cleaner: More useful than the traditional spongy cleaner that comes with the soldering station.

Vacuum Pickup Station: Extremely useful for pick&place of the tiny resistors, capacitors etc. Although my 0603 size resistors were too small for the smallest vacuum suction tip that this kit has. It sucked up 3 of the resistor and I still can’t find them! So I ended up using the tweezer for the resistors (painful). I need to find smaller tip for vacuum suction.

Flux Paste: This is your best friend!

Wipers: Needed to cleanup after soldering.

Flux Brushes: Needed to cleanup after soldering.

How to SMD Soldering
Soldering QFN Components
How to use Vacuum Pickup Tool

My begineer soldering kits
Soldering Station
Helping Hand
Desoldering pump


Open Hardware Summit 2014

I attended Open Hardware Summit this September in Rome, Italy. It was a two day conference with great speakers – Adrian Bowyer, Eric Pan, Becky Stern, Jason Kridner, Micah ScottMadeline Gannon, Zack Jacobson-Weaver, JeromeAmmar Halabi, Yasmin Elayat, Liat Brix, Hagit Keysar, Allison Burtch, Jason Kridner  and more.

Addie starts the Day1 of the Summit

Madeline Gannon and Zack Jacobson-Weaver on open source industrial robots

Eric on Design from Manufacture

On day 2, Benjamin had the workshop on open hardware business model.
Eric had another interesting workshop  on design from manufacture.

I got the opportunity to co-chair the Summit along with Addie, Simone, Zach and Gabriella.


Mathilde from Making Society has published a great recap on the summit.
And checkout the Flickr photo stream of Open Hardware Summit 2014.


RaspberryPi: Reading I2C Inputs using C

Accessing Raspberry Pi GPIO pins with Python libraries is popular among hackers & makers. How about programming languages like C? C gives you flexibility to port code in embedded firmware/driver layer if necessary. That is why I was looking for a C library that exposes Raspberry Pi GPIO pins for application layer. I was specially interested in exploring the I2C pins and found the excellent wiringPi library.

In this post, I will show step by step on how I use wiringPi library to read from the I2C interface of a 3-axis Accelerometer+Gyroscope module. The module I used is GY521 (InvenSense MPU6050).

Hardware setup:

I have a Raspberry Pi Model B (Rev-1), GY521 (InvenSense MPU6050), breadboard & some male-female wire.

*Connect Raspberry Pi 3V3 to GY521 VCC
*Connect Raspberry Pi GND to GY521 GND
*Connect Raspberry Pi SCL to GY521 SCL
*Connect Raspberry Pi SDA to GY521 SDA

To find the Raspberry Pi GPIO pin maps, follow this guide


*Install I2C dev library. Under Raspbian, use

sudo apt-get install libi2c-dev

*Configure I2C pins using adafruit guide

*Install wiringPi using this link

*Make sure your Raspberry Pi can detect the device attached to the I2C interface. If detected, then you will see an address with below command. In my case, the address is 0x68 which is then used in the code.

i2cdetect -y 0 # Rev 1
i2cdetect -y 1 # Rev 2

*Use this sample code from my github

*Use the Makefile and type

$make i2ctest
$sudo ./i2ctest

You should now see the sensor data value in the screen.


Bluetooth Low Energy: Read-Write to Sensor Network from Raspberry Pi

In this tutorial, I am using a RedBearLab Bluetooth Low Energy (BLE) shield connected to Arduino UNO to demonstrate the BLE communication from Raspberry Pi.

  • Install hard-float Raspberryian OS using this link.
  • Install Bluez using step 1, 2, 3 of this link.
  • I used CSR 4.0 dongle in the Raspberry Pi for BLE connection.
  • Make sure you have gatttool in the path using
    $which gatttool
    If it is not in the path, copy it from bluez/bluez-5.11/attrib
    $cp bluez/bluez-5.11/attrib/gatttool /usr/local/bin/
  • Check if the Bluetooth dongle is up and running
    ~/bluez/bluez-5.11 $ tools/hciconfig
    If not (you will see DOWN written in the result), use below command to get it up
    ~/bluez/bluez-5.11 $ tools/hciconfig hci0 up
  • Now scan for BLE devices. The command below might continue scanning forever, so type CTRL+C when you have the device address
    $ sudo hcitool lescan
    Assume you get the BLE device address xx:xx:xx:xx:xx:xx
  • Now connect with the device using gatttool
    $ sudo gatttool -b xx:xx:xx:xx:xx:xx -t random –interactive
    You might not need to use -t random. Also if you get device busy error, remove the dongle and reconnect it.  You will see an interactive prompt. Type connect like below
    [xx:xx:xx:xx:xx:xx][LE]> connect
    Attempting to connect to xx:xx:xx:xx:xx:xx
    Connection successful

Once it is connected, we want to write to a LED to turn in ON/OFF, and read the sensor data. We are using FSR as the sensor in this example. We will use gatttool to do the read & write.

Before we begin, we need to understand how this works fundamentally. You can go ahead and read this book or any other good tutorial that I am not aware of. But basically, you need to have some code on your Arduino that sets up a profile in the nRF8001 component on your RedBearLab shield that defines “pipes” which is the link between a characteristic exposed by the radio and a function from which you can read data or to which you can send data.

I am using SimpleControl sketch from RedBearLab as the code that runs on Arduino.  To do read-write, we need to know which address to write and what value to write.

Find the Address to Read & Write: 
I look at RedBearLab’s Android source code to figure out the TX, RX address.  In the RBLGattAttribute.java, you will see

public static String BLE_SHIELD_TX = “713d0003-503e-4c75-ba94-3148f18d941e”;
public static String BLE_SHIELD_RX = “713d0002-503e-4c75-ba94-3148f18d941e”;

Now, if you type below in the gatttool interactive prompt, you can figure our the address (handle) of those TX, RX

[xx:xx:xx:xx:xx:xx][LE]> char-desc
handle: 0x000b, uuid: 713d0003-503e-4c75-ba94-3148f18d941e
handle: 0x000c, uuid: 2803
handle: 0x000d, uuid: 713d0002-503e-4c75-ba94-3148f18d941e
handle: 0x000e, uuid: 2902

So you basically see that the handle of TX, RX are 0x000b and 0x000d respectively.

How to Turn ON/OFF the LED:
From the SimpleControl.java, you can see that you need to write 010100 to the TX handle to turn the LED ON and 010000 to turn it OFF.

digitalOutBtn.setOnCheckedChangeListener(new OnCheckedChangeListener() {
public void onCheckedChanged(CompoundButton buttonView,boolean isChecked) {
             byte buf[] = new byte[] { (byte) 0x01, (byte) 0x00, (byte) 0x00 };
             if (isChecked == true)
                  buf[1] = 0x01;
                  buf[1] = 0x00;

Now type below to turn the LED ON
[xx:xx:xx:xx:xx:xx][LE]>char-write-cmd 0x000b 010100

To Read Analog Data: 
Similarly from the SimpleControl.java, you can see that you need to write A00100 to the handle 0x000b to enable the analog reading capability through the RedBearLab shield. You also need to enable listening to the 0x000e handle. The 0x000e is the handle of the Client Characteristic Configuration (CCC) uuid 2902. You can find this 0x000e handle by typing char-read-uuid 2902 in the gatttool interactive prompt.

[xx:xx:xx:xx:xx:xx][LE]>char-write-cmd 0x000b A00100
[xx:xx:xx:xx:xx:xx][LE]>char-write-req 0x000e 0100 –listen

You will see sensor values in coming the the RX handle (0x000d)
Notification handle = 0x000d value: 0b 00 c0
Notification handle = 0x000d value: 0b 00 d0
Notification handle = 0x000d value: 0b 00 e4
Notification handle = 0x000d value: 0b 00 f0