Reading Simulations

Identify the Gate

Read a captured input/output table from a simulation and figure out which 2-input gate produced it.

Infer the Counter

Infer a synchronous counter's reset and increment behavior from a recorded cycle-by-cycle sequence.

Infer the Mux

Read an exhaustive input/output table for a three-input circuit and recognize it as a 2-to-1 multiplexer.

Infer the Edge Detector

Infer a rising-edge detector's one-cycle memory from a recorded input/output trace.

Find the Bug: 2-to-1 Mux

Repair a selector whose two data inputs are swapped.

Find the Bug: NAND Gate

Correct an inverted two-input AND function.

Find the Bug: 4-to-1 Mux

Fix a four-way selector with incorrectly decoded select bits.

Find the Bug: Add/Subtract

Implement unsigned add/subtract selected by a control bit.

Find the Bug: Case Decoder

Repair a decoder so each selector value activates the matching one-hot output.

Combinational Circuit 1

Infer a three-input odd-parity circuit from its input-output behavior.

Combinational Circuit 2

Infer a three-input majority function from a truth table.

Combinational Circuit 3

Infer two comparator outputs from observed two-bit input combinations.

Combinational Circuit 4

Infer an even-width parity function from a waveform.

Combinational Circuit 5

Infer a two-to-four decoder from its observed waveform.

Combinational Circuit 6

Reconstruct a two-bit unsigned adder from observed input and output values.

Sequential Circuit 7

Infer an enabled D register from a clocked waveform.

Sequential Circuit 8

Reconstruct a two-bit modulo-four counter.

Sequential Circuit 9

Infer a four-stage serial-in shift register from its timing trace.

Sequential Circuit 10

Reconstruct a Moore sequence detector for pattern 101.