s address and interrupt wiring:
</p>
<pre>
   {
      pca9555: [
         {
            i2c: 0,          // I2C bus number - 0 for I2C0, 1 for I2C1
            addr: 0x20,      // chip address, set by the A0-A2 pin wiring on the chip
            interrupt: 23,   // GPIO port connected to the chip's INTERRUPT pin
         },
      ],
   },
</pre>
<p>
   The <tt>pca9555</tt> property is an <b>array of objects</b>, with each
   entry in the array representing one chip.  The array lets you configure
   as many 