1、-No.1 2 3 4 5 6 7 8 9- Points：-(1) A quantity having discrete(離散的) values is-學(xué)-線(3) Which of the following is an （無(wú)效） BCD code-級(jí)-訂裝業(yè)-(6) The inputs to a full-adder are A = 1, B = 1 and C = 0. The outputs arein(a)Sum = 1, C = 1(b) Sum = 1, C = 0outout(c)Sum = 0, C = 1(d) Sum = 0, C = 0outout(7) The d

2、evice used to convert a binary number to a 7-segment display format is(a) multiplexer (b) encoder (c) decoder (d) register(8) A modulo-12 counter （12 進(jìn)制計(jì)數(shù)器）must have(a) 12 flip-flops (b)3 flip-flops (c) 4 flip-flops (d)synchronous clocking(9) A 4-bit binary up/down counter is in the binary state of

3、zero. The next state inthe DOWN mode is(a) 0001(b) 1111(c) 1000(d) 1110(10) What is the （分辨率）, in percent, of a 8-bit DAC(a) 0.1% (b) 0.392% (c) 1% (d) 3.92%2. Simplify the following expressions as much as possible.（10 points）) F1F 22 / 83. Design the logic circuit to control the motor on a simplere

4、mote control car. There are two buttons on the remotecontrol for the motor. If neither button is pressed, the car stops. If the topbutton is pressed, the car moves forward. If the bottom button is pressed, thecar moves backwards. If both buttons are pressed, the car spins clockwise( 順時(shí)針旋轉(zhuǎn)). There ar

5、e two motors（left and right） in the car and each motorhas two inputs F(forward) and B(backward). A high on F makes the car goforward. A high on B makes the car go backward. （10 points）(1) Make a truth table for this design.Top BottomStateStopBackwardForwardSpin(2) Implement the circuit by using only

6、 NAND gates.3 / 84. Show how the expression F(X,Y,Z)be implemented using:（10 points） (1,2,4,7) can(1) A 3-8 decoder 74LS138 with some gates as needed.(2) A dual 4:1 multiplexer 74LS153 .4 / 85. The JK flip-flop is negative edge triggered. Assumingthe initial state of A is 0 at t=0, give the expressi

7、ons of 、B ，and sketch the waveforms of A and B.（10 points）AJQQBCPCCPABK6. Analysis the circuit below, draw the state diagram anddetermine the modulo of this counter. (10 points)3Q210&CRD LD EP ET D3 2 1 0” ” ”5 / 87. Design a modulo-7 counter using a 74163 IC, which willShow 1-7 in LED display. (10

8、points)0123C01238. Create an astable multivibrator(多諧振蕩器) using a 555timer. The output frequency is 20 kHz. If the externalcapacitor C is 0.002F and the duty cycle is 75%, determine the values ofthe external resistors. （10 points）76216 / 89. The pin diagram of 74LS00 are given below. Constructthe circuit to implement the logic function F = AB + ACusing a single 74LS00 IC. (10 points)Data Sheet:741382 A1 A Y Y Y Y Y Y Y Y0230123456701111111110110111111111101111111111011111111110111111111101111111111011111111110