Consider a $12-$bit hypothetical machine that contains a single data register, called an

accumulator $($AC$)$ with the following characteristics:

Both Instructions and data are $12$ bits long. For the I$/$O Instructions the $9-$bit address identifies a

particular I$/$O device. Note: Answers in Hexadecimal Digit Only.

What is the number of I$/$O devices can you connect to this hypothetical machine?

Answer: