Digital Logic and Systems Flashcards
7 cards from real BEE practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Digital Logic and Systems flashcards as text
Which number system uses base 16 and includes digits 0-9 and letters A-F?
Answer: Hexadecimal
Hexadecimal (base-16) uses digits 0–9 and letters A–F to represent values 0–15 in a single digit, commonly used in digital systems.
A D flip-flop is triggered on the rising edge of the clock. If D=1 at the rising edge, the next state Q+ is:
Answer: 1
A D flip-flop copies the input D to the output Q on the active clock edge, so Q+ = D = 1.
What is the 2's complement representation of -6 using 4 bits?
Answer: 1010
+6 in 4 bits is 0110; inverting gives 1001, adding 1 yields 1010, which is the 2's complement of -6.
Which combinational circuit converts a binary code to a one-hot encoded output?
Answer: Decoder
A decoder takes an n-bit binary input and activates exactly one of 2ⁿ output lines, producing a one-hot (active-high) output.
In digital logic, glitches (hazards) in combinational circuits are caused by:
Answer: Unequal propagation delays through different paths
Glitches occur when signal transitions take different amounts of time through alternate paths, causing momentary incorrect output values.
What is the function of a priority encoder with inputs I0–I3?
Answer: Outputs the binary code of the highest-priority active input
A priority encoder resolves simultaneous active inputs by outputting the binary code corresponding to the highest-priority (usually highest-numbered) active input.
An SR latch built from NOR gates has an undefined (forbidden) state when:
Answer: S=1, R=1
When both S=1 and R=1 in a NOR-based SR latch, both outputs are forced to 0, violating the complementary output requirement and creating an undefined next state.