Re: More Rotary Encoders

At 03:36 PM 8/4/97 -0800, you wrote:
>>In all the recent discussions about rotary encoders, I don't think I ever
>>saw anyone mention Cinematronics. The reason this comes to mind now, sev-
>>eral weeks later, is that I just started work on connecting a Boxing Bugs
>>board set to my Cosmic Chasm. Both of which use rotary encoders, neither
>>of which were mentioned above.
>
>Ahhh! More to the list!
>
>Well, I took a look at this this last weekend (too hot to work in the
>garage or outside so I had to find something indoors where the AC is :-)
>and have the following operational:
>
>Processor: PIC 16C54 (since I had the nice Windows based simulator I had
>to use it... ;-)
>
>Code is currently at 134 words (of 512 total). It supports the following:
>
>Input: quadrature signal (2 lines TTL level), 2 mode select lines
>Output:
> Mode0: "raw" 8-bit count (like TRON)
> Mode1: "G-80" 7 bit count plus direction bit
> Mode2: "Omega Race/Clk&Dir" 6 bit grey-code. Also clock&direction
> Mode3: TBD
>
>Now then, I need a little help/advise... What four modes should I pick to
>support? Looks like there's some more possibilities--
>
> Midway "Kick" four bit something or other. Anyone have a schematic?
> Cinematronics spinner. (That is, if it's other than quadrature)

The Cinematronics spinners are off the shelf shaft encoders, while I haven't
looked I'm sure finding a replacement for these would be easy. They just
look and feel like a standard pot. They output standard quadrature signals.

I'm not sure where the decoding is done on Cosmic Chasm, but it's not done
inside the spin knob.

On Boxing Bugs it's done on the Sound Board. If you wanted to set it up so
that the outputs of your PIC connected directly to the inputs of the C-CPU,
you'd need to convert to an 8 bit absolute count (0-255 with wrap around)
and you would have to have an extra inputs that latched the current value
(just keep it from being updated) and allowed the cpu to select the upper or
lower nibble of the count, since it only reads 4 bits of the count at a time.

The Boxing Bugs sound board schematic is now on www.spies.com.

-Zonn
Received on Mon Aug 4 15:54:26 1997