Dynamite with a Laser Beam
I always considered constructing a Laser Display Controller using the PSoC 4 if time permitted. Time permitted and so I did. Above are my initial results. I was quite surprised to see how well it worked considering it worked first go especially where critical real time response was essential.
What's more, rather than producing boring Lissajous or Bowditch figures consisting of circles and sine waves that can be generated using a standard signal generator I decided that to use a pentagram as my initial test pattern.
My design consists of only two external components being two 10k resistors. The remainder of the design is within the PSoC 4.
I used its two Current DACs and two Op Amps to produce the required unamplified interface signals for the initial tests.
The 10k resistors are used to convert the current generated from the Current DACs into an output voltage. The Op Amps are configured in unity gain mode to act as signal buffers to prevent the interface load affecting current to voltage conversion.
Conversion from current to voltage is based upon Ohm's law where Vout = I x R.
I hooked the outputs to my DSO configured in XY mode to emulate a simplified ILDA interface Laser Display.
This configuration enables me perform laser display content editing without having to connect up my ILDA interface Laser Display.
True ILDA interface levels can be accomplished with the addition of suitably configured op-amp IC such as an LM324.
An ILDA interface also supports an intensity signals. This feature was not necessary for this simple version because it is not required for driving a DSO.
Driving a ILDA interface display is really nothing more that feeding in X and Y and intensity values as differential voltages in real time. Additional information such as colour selection can also be conveyed according to the Laser Display's capabilities.
