Good morning John,

Great question! A signed 16 bit integer has a range of -32768 to +32767.

That might seem odd at first, but keep in mind if all bits are 1 the resulting number has to be an “odd” number as the first bit's value is “1”, while the rest are even numbers (2, 4, 8, etc)

Also keep in mind that 0 to 32767 is the positive range, while -1 to -32768 is the negative range.

Hope this helps,

Shawn Tierney,
Instructor at The Automation School