The 74138 is a 3-to-8 decoder. Together, two of these ICs can be used to form one 4-to-16 decoder. To do this, connect ()
A. one decoder to the LSBs of the input; the other decoder to the MSBs of the input
B. all chip-select lines to ground
C. all chip-select lines to their active levels
D. one chip-select line on each decoder to the input MSB
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A 4-bit parallel-in/parallel-out shift register will store data for ().
A. 1 clock period
B. 2 clock periods
C. 3 clock periods
D. 4 clock periods
A 3-bit binary counter has a maximum modulus of ().
A. 3
B. 6
C. 8
D. 16
An asynchronous counter differs from a synchronous counter in ().
A. the number of states in its sequence
B. the method of clocking
C. the type of flip-flops used
D. the value of the modulus
There are at least ()flip-flops for a modulus-12 counter.
A. 12
B. 3
C. 4
D. 5
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