Before revision: In digital electronics three-state, tri-state, or 3-state logic allows an output or input pin/ port to assume a high impedance state, effectively removing the output from the circuit, in addition to the 0 and 1 logic levels.
After revision: In digital electronics three-state, tri-state, or 3-state logic allows an output or input pin/ pad to assume a high impedance state, effectively removing the output from the circuit, in addition to the 0 and 1 logic levels.