The HL1606 chip supports the cascade connection of comparable ones, thus allowing to create strips with a very high number of channels. Each strip controller’s output guides the LEDs with PWM signals, so to modulate the brightness in the most efficient way, and to enable all the possible colour hues.
As regards the step by step motors driver, in the shield’s plan it is signed as U1; the module is essentially an A4988 integrated circuit from Allegro, and a very adaptable one since it can be set so to define both the rotation direction of the driving shaft, and the number of degrees that the motor’s rotor has to make when receiving each command. In other words, when we give a command impulse we may decide if the module has to rotate the drive shaft one step at the time, or by 1/2, 1/4, 1/8 or 1/16 of step, depending on the accuracy we want to achieve.
Under the carriage is fixed and the chain grommet retainer strap, whose most advanced actuate the switch lever switches.
As regards the LEDs to be put under the glass, they are assembled in a ring using Neopixel technology (marketed by www.adafruit.com with the WS2812 5050 code) with 16 RGB light-emitting diodes that can be individually managed: each one of them can produce 256 tones of its colour, thus determining a total of 16.777.216 colours. Neopixel is the solution that considers the integration of a driver and of the relative RGB LED within SMD, and thus the direct command operates LED by LED. The LED scan frequency is 400 Hz, as for the strip. The data channel for communication is a serial one, of the oneWire kind, and the power supply is 5 V; the communication happens with a maximum of 800 kbps. As regards the LED ring it is possible to set the refresh frequency at leisure, so that certain types of light-games are not perceivable. More rings may be connected in cascade, to create various effects, but in this case we are not interested in such a configuration. Keep in mind, however, that the more are the rings connected to a single data channel, the more the refresh frequency will be limited, if keeping the maximum data-rate constant.
The tapster has an inlet with rubber seal multilabbro and a button by pressing which the nozzle dispenses the predetermined quantity.
The ring command protocol considers that groups made by three bytes are sent within a 24 bits string: each one of them contains the lighting status of each base colour (first the green’s eight bits, then the ones for the red, and finally the ones for the green).
