Last year, Sub-Etha Software “announced” the Sir Sound, a sound add-on for the Radio Shack Color Computer that would plug in to the Serial I/O (i.e. printer or bitbanger) port. The prototype looks like this:
The idea was, by making this device “smart”, you could send simple, small commands to it and it would take care of the actual music playing, freeing up CPU time for the program. Since the device was “smart,” firmware could also be expanded with new features added.
The plans will be available for anyone who wants to build their own, and the source code will be posted to my Github repository. For someone like myself, with little or no hardware skills, you will be able to build this just by plugging wires into a breadboard (like the prototype). It’s not pretty, but it’s cheap and easy. And fun!
Various Sir Sound options…
I have contemplated designing a custom board for this, which would have a handful of chips and parts on it as well as a serial port and USB plug. Basically, it would be a board version of the prototype. The cost on this would be pretty low, but since I am not a hardware guy, I likely wouldn’t want to be the one soldering all the parts together.
Another option would be to just make an Arduino Shield that plugs in to a cheap Arduino UNO clone. You can get a good-quality Arduino for around $6, shipped from the USA by resellers on e-Bay. This could make the cost of the “Sir Sound” portion lower, though you’d still need an Arduino. You can buy a fully-made Arduino for less than the parts to build a clone, so this seems like a good way to reduce costs.
So which is better: Full board with everything, or add-on Shield for an Arduino?
I am not sure if the cost of the Arduino header pins is more expensive than the few chips it takes to just make the Arduino circuitry on a standalone board ;-) But, for folks who already have an Arduino, the add-on Shield is a great way to re-use existing hardware (and you can then use it for other projects when you are not hooked up to the CoCo). And, even for for those who don’t already have an Arduino, it might still be cheaper than the fully custom solution.
Sound + WiFi?
But what if it could do more than just sound?
Recently, I started playing with the ESP8266 WiFi chip. This device has a built in networking stack and WiFi hardware. It also has RAM and flash storage, and you can load it with custom firmware. This module is cheap! I ordered a “developer kit” with a USB port for less than $9 from Amazon.
See those pins on the bottom? These developer modules make all the I/O lines available, it would be possible to make a small board with the sound chip and serial port on it that this plugs in to. This could give you sound and WiFi!
For the bitbanger serial port, baud rate on WiFi and Bluetooth would be limited to a slower speed, but if could also be plugged up to an RS232 Pak for high speed networking.
And, this looks like it would be cheaper than using an Arduino! More features for less money?
And, for a few bucks more, there is a module that adds Bluetooth as well, giving you sound, WiFi and bluetooth!
To be continue…
Let’s just say there are a few prototypes in the works right now… And they are all very cheap.
More to come…