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WHAT'S YOUR ENGINEERING QUOTIENT?

Problem 1—What is the function of switch S1?

ANSWER

Problem 2—What is wrong with following display driver algorithm?

Assume cathode driver port is left justified and shift operation fills with zero. Assume stated cathode addressing is correct.

	Set both output ports to zero.
LoopStart: Output digit 1 decoded value to anode port.
Output decimal 8 to cathode port.
Output digit 2 decoded value to anode port.
Shift cathode port right.
Output digit 3 decoded value to anode port.
Shift cathode port right.
Output digit 4 decoded value to anode port.
Shift cathode port right.
Jump to LoopStart.

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