Embedded Gardening, Part 4 - Perf Proto Boarding

Solderless protoboard is fast and flexible, but the connections can be flaky and the wires can pull out if you move it around.  I wanted to move it to something a little more permeant.

I needed a way to keep track of the wiring, so I downloaded and learned how to make a basic schematic in EasyEDA.  It was really pretty easy, at least for the diagram.  I'm expecting layout to be more challenging.

I cleaned up my wiring diagrams a bit before doing the protoboard.  Here is the diagram:



This included the new MCP23008.  And to be honest, for the extra cost, since I only needed one more  GPIO with interrupt support, v2 will just use a board with more GPIOs.  Bringing in another driver brought a series of difficulties that I'll discuss later.

You'll may notice the buck converter is missing from the diagram.  At the time, I only had parts for one board and I was concerned about wiring up the converter wrong and toasting the ESP8266.  In the prototyping I brought in 12v power to the converter, but did not wire it into the chip.  When I get the next version running, I'll hook it up and see if it works.

Below is the proto perf board.  Coming out the right are wires heading out to the flow sensor.

On the bottom are JST connectors connected to the soil sensors.  But empty JST connectors on the lower right for the temp/humidity/pressure + brightness sensors.

The JST crimper and set I bought was mostly a fail.  I just could not get good crimps from it.  I used the JST sockets and used the JST plugs + wires that came with the soil sensors.  I didn't have any premade that I would extend for the other sensors.  I also didn't have any additional plugs for the 5V flow sensor, so I hard wired those wires.  The plan for next time is likely to buy some pre-wired JST connectors that I can just extend as needed for the sensors.  I'm just not up for another JST catastrophe quite yet.

I used 12V barrel connectors I had on hard for the 12V in to the relay and 12V out to the valve.  

 

Here's a closer-up with the pats labeled.








In the next installment I'll cover the software prototyping and development.

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