E E 319K Quiz: EE319K Quiz1AF12sol
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B) we could decrease the frequency of the bus clock (4) question 2. 33 32 31 30 = 27, 9, 3, 1 (3) question 3. R3 is 150, which is 128+22=128+16+6=128+16+4+2 = 0x96. Convert both to signed 50 - -100 = 150, which doesn"t fit, so v=1. (20) question 4. Since led current is less than 8ma, we can drive it from the microcontroller. R = (3. 2-1v)/2ma = 2. 2v/2ma = 1100 . The switch doesn"t need a resistor because of the internal pull down. Write an assembly subroutine that selects bit 8. The input to the subroutine is a 32-bit number in r0. The output in r0 is 0 if the input bit 8 is 0, and the output is 1 if the input bit 8 is 1. Mask8 and r0,r0,#0x00000100 ;remove all bits except bit 8. Lsr r0,r0,#8 ;move bit 8 into bit 0 position. The input to the function is an unsigned 32-bit number.
