pc87591l National Semiconductor Corporation, pc87591l Datasheet - Page 151

• Manufacturer Part Number: pc87591l
• Description: Lpc Mobile Embedded Controllers
• Manufacturer: National Semiconductor Corporation

Revision 1.07
Embedded Controller Modules
4.9
The USART is a full-duplex synchronous/asynchronous receiver-transmitter that supports a wide range of software program-
mable baud rates and data formats. It handles automatic parity generation and several error detection schemes. DMA trans-
fers are supported to enable fast processor-independent receive and transmit.
4.9.1
4.9.2
The USART is composed of the following functional units:
Figure 52 shows a block diagram of the USART.
Full duplex double-buffered receiver-transmitter
Synchronous operation
Asynchronous operation
Programmable baud rate between CLK/2 and CLK/32768 baud
Numerous framing formats
— seven, eight or nine data bits
— one or two stop bits
— odd, even, mark, space or no parity
Hardware support of parity-bit generation during transmission and parity-bit check during reception
Interrupt on transmit buffer empty, receive buffer full and receive error conditions with separate enable
Software-controlled break transmission and detection
Software-controlled reset, enable/disable
Internal diagnostic capability
Automatic error detection
— Parity Error
— Framing Error
— Data Overrun Error
9-bit Attention mode
DMA support for transmit and receive with separate enable
Transmitter
Receiver
Baud rate generator
Control and error detection
UNIVERSAL SYNCHRONOUS/ASYNCHRONOUS RECEIVER-TRANSMITTER (USART)
Features
Functional Overview
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