So. I’ve recently worked out how to get an alternate audio module working for the various circuits.
But Why? I hear you asking(1)
Simples. 
Cost.
The previous circuits used the DFplayer audio 
module. Which work out at a round a little over £1 each, depending on 
the exchange rate. The new modules, cost a little bit more, but not by much.
HOWEVER. The new modules have onboard Flash Memory 
whereas the DFPlayer modules use microSD cards. Which increase the cost 
substantially. It’s fine when your making just one or two things, but 
the last big project for Babylon 5 earlier
 this year, needed around 50 audio modules. That’s a LOT of extra money 
to find.
The only possible concern is the capacity of the 
flash memory – I’ve not fully checked out how much it can hold yet. They
 are also slightly larger, and a different pin layout which is more of 
an issue when working with Veroboard, as when
 I get the professionally made boards designed and sorted they are a lot
 easier to fit on. Even if it’s looking like I’ll have to do the design 
work and layout for the module myself for using in EAGLE PCB software 
(straight forward enough as I can start of
 with the DF player and edit it)
So, along with the change to Pic chips, the new 
audio modules with drastically lower the basic cost of emitter or sensor
 circuits by a good £3-£6 each.
I’ve not done the full working out yet, but I’m 
hoping, when everything is finally ready and released open source, to 
also be able to offer pre-programmed Pic chips, or Pre-flashed sound 
modules as well as professionally etched boards,
 and fully assembled boards for as close to £10-£15 each as possible for
 the emitters and whatever it works out at for the sensors.
Essentially, as well as the plans and both hex 
files and code to build the things to be able to offer kits, or 
pre-built circuits that just need the various buttons and speakers 
attaching (I’m thinking of including the Emitters, as the
 ones I use, weirdly have the legs setup so that positive/negative are 
indicated the opposite way round to pretty much every other LED I’ve 
seen… Or at least, pre-wired emitters with the traditional red/black for
 positive/negative.
But that’s for the future. In the meantime, the 
only separate thing I need to sort out for the pic circuits, before 
smooshing it all together in the code is counting the pulses to check 
the frequency….
And I’d have had that done by now if I wasn’t waiting for new IR receivers to arrive(4)
1: I do…. I can hear EVERYTHING(2)
2: Or I may just be overtired and having audio-hallucinations.. Hey-ho
3: Normally, positive is on the longer leg, negative on the shorter… Not on these puppies.. Oh no….
4: So, it turns out, that if you accidentally wire 
the +ve and -ve on an IR receiver backwards on your development 
breadboard and blow it… It’s a good idea to correct the wiring before 
going “Oops” and just replacing the blown one with
 the last one you’ve got in the house…..

 









