Driving a control line or bus signal to its active, true state to trigger an action. In positive logic, this means pulling the line to a high voltage. In negative logic systems, a signal is asserted by pulling it down to zero volts. Designers use this term to avoid the confusion of saying a line is turned on or driven high when the active state might actually be low.
Make sure you assert the chip select line before trying to clock data into the register.
Always check the datasheet for a bar over the pin name, which indicates the pin must be pulled low to assert it.
Related terms
Logic high
The higher of two voltage states used to represent a binary one in a digital circuit.
Logic low
The lower of two voltage states used to represent a binary zero in a digital circuit.
Positive logic
A digital design convention where the higher voltage level represents a binary one.
Negative logic
A digital design convention that assigns the true state to a low voltage and the false state to a high voltage.