I don't remember exactly how we got to the point where we came up with the idea to make it into a modular platform, but it had something to do with the ATtiny4313 I think, sounded like a good idea to make it more versatile!
Why stop at making a wireless firing system, right?! 😉

fireCrow: first draw

The firing system was originally designed for squibs (SFX body hits), so it's very important that the size is as small as possible to be easily concealed under the actor's clothes.

At first we were stuck with the idea of a wireless firing system, but when we found the ATtiny4313 with "a lot" more memory (4K instead of 2K) than the ATtiny2313, we started to fantasize about what could be done with all that space!

As I said before, why make a closed platform like a firing system when you can make something that a wider range of people can use, like a versatile micro controller with plug-in cards?

Said and done, I started to draw a real schematic (not like the old ones made in paint) in Cadsoft Eagle. After the schematic was done I moved over to the PCB design, there was a lot of redrawing done before I ended up with the final design of fireCrow v1.0.

Below you can see how it evolves and gets cleaner (top left 1st, bottom right final):

When the design was done I sent my files to seeedstudio for manufacturing.
I was very pleased when the PCBs finally arrived to me:

Of course we found a design flaw that slipped through. The voltage regulator I'd chosen had shifted V-in and V-out on the footprint, and the RX and TX LED didn't work as assumed (always on).

We switched the voltage regulator for a better one (with more mA) and just skipped the RX and TX LED on the next PCB assembled.
Not too bad for a first time PCB design if you'd ask me!

Here is the fireCrow v1.0 soldered and ready to get its firmware flashed:

The next step was to build the remote control, or the fireNest as we named it. 😎
Actually, I built a prototype remote with a Arduino FIO as brain, so David could easily get started with the firmware testing.

Here are some photos from the build:

Wiring of push buttons and LEDs:

FIO in place and fitted inside the box:

Almost finished:

Everything in place! Actually the ON LED gives a nice visual feedback inside your palm when holding it, no need to look at the led:

After a little tampering with the firmware, David got it to work as it should:

What you see is the remote control scanning for the receiver when turned on.
All LEDs flashing means the receiver is found and identified, then what follows is a simple firing test with the receiver hooked up to some LEDs.

One of the last things I did before starting with v2 was a 2 channel prototype plug-in card:

Later on I managed to fit continuity check for both channels, a very desirable feature when it comes to pyrotechnics 😉

Here is a 75 meters range test we did:

And here is another test at 25 meters:

Here is a size comparison with a professional 6 channel squib system, called Holatron, and our fireCrow v1.0 with the 2 channel plug-in card:

Afterwards, David and I had a meeting with Lennart, from the Gothenburg Opera House, and David Peter, the pyrotechnician next-door, about the fireCrow and what they liked and did not like with the system, and what could be improved. We had a lot of new ideas how to refine the fireCrow and go on to version 2.

So this is the end for v1.0! But the story goes on...
...in another post 😉

Don't miss how it all started!
Also, take a look at the technical overview of the fireCrow v1.0