UART Controller Block Diagram and System Integration
Figure 21-1: UART Block Diagram
Serial Transmitter/
Receiver
Interrupt and System
Reset Control
FIFO Buffer
Baud Clock
Generator
DMA
Interface
Register Block
Slave Interface
UART Controller
To I/O
Pins
RX
TX
RTS
CTS
L4 Peripheral Bus
MPU
IRQ
DMA
Controller
Clock
Manager
Reset
Manager
Table 21-1: UART Controller Block Descriptions
Description
Block
Slave interface between the component and L4
peripheral bus.
Slave interface
Provides main UART control, status, and interrupt
generation functions.†
Register block
Provides FIFO buffer control and storage. †
FIFO buffer
Generates the transmitter and receiver baud clock.
With a reference clock of 100 MHz, the UART
controller supports transfer rates of 95 baud to
6.25 Mbaud. This supports communication with all
known 16550 devices. The baud rate is controlled by
programming the interrupt enable or divisor latch
high (
IER_DLH
) and receive buffer, transmit holding,
or divisor latch low (
RBR_THR_DLL
) registers.
Baud clock generator
Converts parallel data written to the UART into serial
data and adds all additional bits, as specified by the
control register, for transmission. This makeup of
serial data, referred to as a character, exits the block
in serial UART. †
Serial transmitter
Converts the serial data character (as specified by the
control register) received in the UART format to
parallel form. Parity error detection, framing error
detection and line break detection is carried out in
this block. †
Serial receiver
UART Controller
Altera Corporation
cv_54021
UART Controller Block Diagram and System Integration
21-2
2013.12.30