Rainbow Electronics Atmega169L - Manual (Page 94)

94
ATmega169V/L
2514A–AVR–08/02
16-bit Timer/Counter1
The 16-bit Timer/Counter unit allows accurate program execution timing (event man-
agement), wave generation, and signal timing measurement. The main features are:
•
True 16-bit Design (i.e., Allows 16-bit PWM)
• Two independent Output Compare Units
• Double Buffered Output Compare Registers
• One Input Capture Unit
• Input Capture Noise Canceler
• Clear Timer on Compare Match (Auto Reload)
• Glitch-free, Phase Correct Pulse Width Modulator (PWM)
• Variable PWM Period
• Frequency Generator
• External Event Counter
• Four independent interrupt Sources (TOV1, OCF1A, OCF1B, and ICF1)
Overview Most register and bit references in this section are written in general form. A lower case
“n” replaces the Timer/Counter number, and a lower case “x” replaces the Output Com-
pare unit channel. However, when using the register or bit defines in a program, the
precise form must be used, i.e., TCNT1 for accessing Timer/Counter1 counter value
and so on.
A simplified block diagram of the 16-bit Timer/Counter is shown in Figure 39. For the
actual placement of I/O pins, refer to “Pinout ATmega169” on page 2. CPU accessible
I/O Registers, including I/O bits and I/O pins, are shown in bold. The device-specific I/O
Register and bit locations are listed in the “16-bit Timer/Counter Register Description”
on page 116.