Uart Ports - Analog Devices Blackfin ADSP-BF537 Hardware Reference Manual

The timer units can be used in conjunction with the UARTs to measure
the width of the pulses in the datastream to provide an autobaud detect
function for a serial channel.
The timers can generate interrupts to the processor core to provide peri-
odic events for synchronization, either to the processor clock or to a count
of external signals.
In addition to the eight general-purpose programmable timers, a 9th timer
is also provided. This extra timer is clocked by the internal processor clock
and is typically used as a system tick clock for generation of operating sys-
tem periodic interrupts.

UART Ports

The processor provides two half-duplex Universal Asynchronous
Receiver/Transmitter (UART) ports, which are fully compatible with
PC-standard UARTs. The UART ports provide a simplified UART inter-
face to other peripherals or hosts, providing half-duplex, DMA-supported,
asynchronous transfers of serial data. The UART ports include support for
5 to 8 data bits; 1 or 2 stop bits; and none, even, or odd parity. The
UART ports support two modes of operation:
• Programmed I/O
The processor sends or receives data by writing or reading
I/O-mapped UART registers. The data is double buffered on both
transmit and receive.
• Direct Memory Access (DMA)
The DMA controller transfers both transmit and receive data. This
reduces the number and frequency of interrupts required to trans-
fer data to and from memory. Each of the two UARTs have two
ADSP-BF537 Blackfin Processor Hardware Reference
Introduction
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