13
AT91R40807
1345DS–ATARM–02/02
User Peripherals
USART: Universal
Synchronous/
Asynchronous Receiver
Transmitter
The AT91R40807 microcontroller provides two identical, full-duplex, universal synchro-
nous/asynchronous receiver/transmitters.
Each USART has its own baud rate generator, and two dedicated Peripheral Data Con-
troller channels. The data format includes a start bit, up to 8 data bits, an optional
programmable parity bit and up to 2 stop bits.
The USART also features a Receiver Timeout register, facilitating variable length frame
support when it is working with the PDC, and a Time Guard register, used when interfac-
ing with slow remote equipment.
TC: Timer Counter The AT91R40807 microcontroller features a Timer Counter block that includes three
identical 16-bit timer counter channels. Each channel can be independently pro-
grammed to perform a wide range of functions including frequency measurement, event
counting, interval measurement, pulse generation, delay timing and pulse width
modulation.
The Timer Counter can be used in Capture or Waveform mode, and all three counter
channels can be started simultaneously and chained together.
