I/O Programming Timer/Counter: Operating Modes

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1. Unit-IV-A On-Chip Peripherals And Programming Embedded Programming: Data Types, Operators Embedded Programming: Data Conversion, I/O Programming Timer/Counter: Operating Modes, Programming. UART:Operating Modes, Programming.

2. A timer in a microcontroller is a hardware component that counts time or increments or decrements at a set rate. Timers are also known as counters.  How does a timer work?  A timer receives a clock signal from the microcontroller It increments or decrements based on the clock signal It can count up or down, depending on how it's configured It can roll over when it reaches a maximum value

3. TMOD (Timer Mode Register) An 8-bit register that controls the operating modes of Timers 0 and 1  The lower 4 bits control Timer 0, and the upper 4 bits control Timer 1  The TMOD register selects the timer or counter and mode of timers  The TMOD register has a gate bit that controls whether the timer is started and stopped by software or hardware  The TMOD register has mode select bits, M1 and M0, that select the timer operations