Gadget, Strike and Dip

Testing the Strike and Dip prototype and exploring the MSP430FR6989

This post was originally published on June 25, 2018 at


I forgot to mention this earlier, but I made a non-connected version the the lamp with a spare Arduino Uno that I had kicking around and sent it to my Dad for Father’s Day.  He’s a Denver Broncos fan so it oscillates from blue to orange and back.  I was pretty pleased with how it turned out, and he thought it was the duck’s guts so I was thankful for that.

On a slightly more depressing bent, I took my Strike and Dip prototype out to McDowell Grove for some field testing.  Let’s just say that it needs some work.  I tested it against a standard analog transit compass and an Android app called PocketTransit.  The caveat on the testing is that since this is Illinois I could not test on any natural rock formations.  I’m not certain if the concrete structures that I tested on were steel reinforced or not, which would throw off pretty much all of the measurements.  The following is based on the analog transit compass as the reference:

Dip Variance Strike Variance
Prototype .75° 15.75°
Phone 2.25° 9.25°

So the dip measurement was pretty well spot on and even better than the app, but in one instance I had a 25° variance on the strike measurement.  That is pretty bad.  I suspect that it is either the possible steel reinforcement or something buggy in my fusion code.   There will be tests in the near future.

The other thing that I’ve been playing with a bit is the TI MSP430FR6989 Launchpad Development Board.  The MSP430 is a line of 16-bit RISC microcontrollers that I’d heard a mix of interesting and disparaging things about.  Being 16-bit it doesn’t have floating point support, but it has a pretty good peripheral set and a chip with built in FRAM seemed interesting to play with so I gave it a go.

Having played with the Arduino IDE where everything is abstracted to the point of ridiculousness  and the STM32 line where quite a bit of the complexity is still abstracted out by the STM hardware abstraction layer, I had a lot of fun learning how to play with this chip!  Like any other microcontroller, it is completely register driven but TI provides hardly any abstraction beyond providing the registers with a name.  Going through the User’s Guide and getting to know the individual bits of the registers and how they all play with each other was a real kick and just getting an LED to blink gave me a sense of accomplishment.  The Launchpad also gives you two buttons and an LCD screen to play with, so the number of things that you can try out with a bare board is vastly more than you can with a bare NUCLEO or most Arduino based boards.

I have one more dev board waiting for me to start exploring it, too.  I picked up my first FPGA!  The Numato Elbert V2 is a slick little board.  It is based around a Xilinx Spartan 3A, which is not exactly a powerhouse as far as FPGAs go, but the number of peripherals built into the board combined with a $35 USD price made it difficult to pass up.  Verilog sounds like it will be a challenge to learn, but I’m really looking forward to starting.