sc16c652 NXP Semiconductors, sc16c652 Datasheet - Page 7

• Manufacturer Part Number: sc16c652
• Description: Dual Uart With 32 Bytes Of Transmit And Receive Fifos
• Manufacturer: NXP Semiconductors

Philips Semiconductors
6. Functional description
9397 750 11634
Product data
6.1 UART A-B functions
The SC16C652 provides serial asynchronous receive data synchronization,
parallel-to-serial and serial-to-parallel data conversions for both the transmitter and
receiver sections. These functions are necessary for converting the serial data
stream into parallel data that is required with digital data systems. Synchronization for
the serial data stream is accomplished by adding start and stop bits to the transmit
data to form a data character (character orientated protocol). Data integrity is insured
by attaching a parity bit to the data character. The parity bit is checked by the receiver
for any transmission bit errors. The electronic circuitry to provide all these functions is
fairly complex, especially when manufactured on a single integrated silicon chip. The
SC16C652 represents such an integration with greatly enhanced features. The
SC16C652 is fabricated with an advanced CMOS process.
The SC16C652 is an upward solution that provides a dual UART capability with
32 bytes of transmit and receive FIFO memory, instead of 16 bytes for the 16C2550
and none in the 16C2450. The SC16C652 is designed to work with high speed
modems and shared network environments that require fast data processing time.
Increased performance is realized in the SC16C652 by the transmit and receive
FIFOs. This allows the external processor to handle more networking tasks within a
given time. In addition, the four selectable receive and transmit FIFO trigger interrupt
levels are uniquely provided for maximum data throughput performance especially
when operating in a multi-channel environment. The FIFO memory greatly reduces
the bandwidth requirement of the external controlling CPU, increases performance,
and reduces power consumption.
The SC16C652 is capable of operation up to 5 Mbits/s with a 24 MHz clock. With a
crystal or external clock input of 7.3728 MHz, the user can select data rates up to
460.8 kbits/s.
The rich feature set of the SC16C652 is available through internal registers.
Selectable receive and transmit FIFO trigger levels, selectable TX and RX baud rates,
and modem interface controls are all standard features. Following a power-on reset or
an external reset, the SC16C652 is software compatible with the previous generation,
SC16C2550 and ST16C2450.
The UART provides the user with the capability to bi-directionally transfer information
between an external CPU, the SC16C652 package, and an external serial device. A
logic 0 on chip select pins CSA and/or CSB allows the user to configure, send data,
and/or receive data via UART channels A-B. Individual channel select functions are
shown in
Table 3:
Chip Select
CSA-CSB = 1
CSA = 0
CSB = 0
Table
Serial port selection
3.
Rev. 04 — 20 June 2003
Dual UART with 32 bytes of transmit and receive FIFOs
Function
none
UART channel A
UART channel B
© Koninklijke Philips Electronics N.V. 2003. All rights reserved.
SC16C652
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