====== Input/Output Circuits ======

==== How to connect LEDs ====

Connect an LED as shown below, and output a logic high to the connected
I/O port to turn the LED ON.

{{ :cubloc:interfacing:interface1.png?nolink |}}

==== How to connect push buttons ====

Connect a push button as shown below, and set the connected port's I/O
mode to input. When the button is pressed, the Cubloc will read logic high;
otherwise it will read logic low.

{{ :cubloc:interfacing:interface2.png?nolink |}}

==== How to connect a potentiometer =====

Connect the potentiometer as shown below to an A/D I/O port and use the
ADIn command to read the position of the potentiometer.

{{ :cubloc:interfacing:interface3.png?nolink |}}

The Cubloc core module uses 5V power. When using a larger voltage,
please use an appropriate voltage converter or regulator.

==== How to Connect an Output Relay ====

The following diagram shows how to connect an output relay to a Cubloc
I/O port. A photocoupler can be used to separate isolate 24V and 5V
circuits and protect against noise. Noise coming from 24V circuit will not
affect the 5V circuit and vice-versa.

{{ :cubloc:interfacing:interface4.png?nolink |}}

==== How to Connect an NPN TR Output ====

This circuit diagram shows an NPN TR photocoupler separating the 5V circuit
from the LOAD.

{{ :cubloc:interfacing:interface5.png?nolink |}}

==== How to Connect a DC24V Input ====

Use a double polarity photocoupler to convert 24V signals to 5V signals.
When input is received, the Cubloc will receive a logic high(5V) signal.

{{ :cubloc:interfacing:interface6.png?nolink |}}

==== How to connect an AD Input ====

To connect an AD input to the CB280, the AVDD and AVREF pins must be
connected to a 5V source. AVREF is the reference voltage that the ADC uses to do conversions.

If a 5V source is connected to the AVREF pin, input voltages from 0 to 5V will
be converted and if a 3V source is connected to the AVREF pin, input
voltages from 0 to 3V will be converted.

The CB220’s AVREF are internally connected to 5V.
The following is the simplest AD input circuit using a potentiometer. When
you turn the knob, the voltage will be converted by the Cubloc ADC to a
digital value from 0 to 1023.

{{ :cubloc:interfacing:interfacead2.png?nolink |}}

The following illustrates a 4-20mA signal connected to the ADC input port.
You can use a 230 Ohm and 20 Ohm resistor in series instead of a 250 Ohm
resistor.

{{ :cubloc:interfacing:interfacead3.png?nolink |}}

For an input voltage from 0 to 10V, use 2 resistors as shown below. This is
called a voltage divider.

{{ :cubloc:interfacing:intefacead4.png?nolink |}}

==== How to use a PWM as Digital-to-Analog converter ====

The Cubloc has 6 PWM ports. If you use a simple circuit like that shown
below, you can make a digital-to-analog converter.

{{ :cubloc:interfacing:intefacedaout.png?nolink |}}