THE 555/4017 WAY OR THE MICROCONTROLLER WAY?
To be honest, I have actually forgotten about this PCB. It was uploaded on the 7th and by the third day, I was notified that the board is on its way to me.
Well, this is going to be something.
This board is a decades long ON and OFF project and I have still not made any decision. Either I use the old skool 555/4017 circuit or solve everything with a microcontroller. Finally, I went with the former but halfway through (like any other Projects, or in layman’s terms, delays), the flow changed. I wanted additional features of bi-colour LEDs, different clock speeds and a relay. At the point of no return, I wished I had used a microcontroller instead.
Here is my reasoning:
Most Tricorders from the TNG series right up to the Voyager, will have at least three PCBs. One for the front scanning array, one for the top panel and lastly, the main body. All the time, I keep thinkng they only use one 555/4017 circuit to synchronise every LED sequence. So when I got my first Playmates Tricorder upgrade from @gmprops in the early noughties, I see that each board has its own 555/4017 or equivalent. And if I so wish, I can actually put that circuit onto one board and using a single wire, synchronise all the boards.
DO YOU WANT FRIES WITH THAT?
Lately, I want to pursue two additional features. The first is the speed change and the second, changing LED colours. This feature comes on when the Tricorder enters into its secondary mode. The original circuit is able to do that, and I just need additional components, actually.
Yes, I can still use the microcontroller to do all that too. In fact, by doing so, it would replace a lot of components from the resistors to the capacitors. Eventually, I would save two ICs, a relay and even more. However, I am very sure there is a trade-off. Although I can synchronise all the boards and keep the component count to a minimum, somehow the cost of a single chip might be on par with the replaced components added together. And you will need to invest in the time needed to create the programs, testing it and yes, programing tools too.
But there is one strong feature which will push me towards the microcontroller: Sound.
THE PROBLEM WITH SOUND
At this time of writing, sound players are my weakness. The Tricorder uses mainly three sounds:
-the opening of the flap
-the scanning worble and,
-the closing of the flap.
So, here are the issues:
When you open the flap, the magnet leaves the reed switch which turns the Tricorder on.
So, it needs to play that first sound, which is the flap opening sound.
The microcontroller needs to know when the sound is finished so that it can play the scanning worble.
And then it needs to know when the worbling sound has reached the end of the file so it can loop it.
Then it also needs to know when the flap is being closed so that it can play the flap closing sound before switching off.
Simple but yet difficult since I have minimal experience in controlling a sound player with a microcontroller. I get get it to play but I cannot get it tell me if a particular file has stopped playing or not. There is a solution for that but I was kinda hoping to use the RS-232 method.
SO WHAT WILL IT BE?
You know, I can go nuts and create two versions:
The 555/4017 with a separate sound controlled by a microcontroller (eventually), and
the microcontroller which SYNCHRONISES and controls EVERYTHING.
And I haven’t even looked at the Tricorder screen animation yet.
It looked more like results from some X-Ray machine. All the layers, from copper-tracks to silkscreen to the pads, etc as in there. It does look messy but once the board arrives, you can visualise it better.
