## Fiber Fun ## Tuesday, October 2, 2018

### Why Is A power Button Symbol A Zero With A One Stuck In It?

"For a CMOS gate operating at a power supply voltage of 5 volts, the acceptable input signal voltages range from0 volts to 1.5 volts for a “low” logic state, and 3.5 volts to 5 volts for a “high” logic state."

HIGH = 1 = ON
LOW  = 0 = OFF

Binary 1 = +3.5 - +5 VDC = ON = HIGH
Binary 0 = 0 VDC - + 1.5 VDC = OFF = LOW

128|064|032|016|008|004|002|001
000|000|000|000|000|000|000|000 = 0
000|000|000|000|000|000|000|001 = 1 ("One" bit is turned on)
000|000|000|000|000|000|001|000 = 2 ("Two" bit is turned on)
000|000|000|000|000|001|000|000 = 4 ("Four" bit is turned on)
000|000|000|000|001|000|000|001 = 9 ("One" bit + "Eight" bit turned on) (1+8)
000|001|000|000|001|000|000|000 = 72 ("Sixty Four" bit + "Eight" bit turned on)(64+8)

If you were to read the voltages in a memory chip address, there would be a series of 1's & 0's, with the 1's represented by a voltage of +3.5 to +5 volts, and the zeroes represented by a voltage of 0 to + 1.5 Volts. You would need a REALLY tiny voltmeter probe, but that's what would be in the chip.

Ones are ON, zeroes are OFF.

Now look at the symbol on your power button. You have the choice of ON or OFF. One or Zero.