23.2.1 Definitions

Many register and bit references in this section are written in general form:
  • n=2 represents the Timer/Counter number
  • x=A,B represents the Output Compare Unit A or B
However, when using the register or bit definitions in a program, the precise form must be used, i.e., TCNT2 for accessing Timer/Counter2 counter value.

The following definitions are used throughout the section:

Table 23-1. Definitions
ConstantDescription
BOTTOMThe counter reaches the BOTTOM when it becomes zero (0x00).
MAXThe counter reaches its maximum when it becomes 0xFF (decimal 255).
TOPThe counter reaches the TOP when it becomes equal to the highest value in the count sequence. The TOP value can be assigned to be the fixed value 0xFF (MAX) or the value stored in the OCR2A Register. The assignment is dependent on the mode of operation.