English
Language : 

D16750 Datasheet, PDF (1/7 Pages) Digital Core Design – Configurable UART with FIFO
D16750
Configurable UART with FIFO
ver 2.08
OVERVIEW
The D16750 is a soft Core of a Universal
Asynchronous Receiver/Transmitter (UART)
functionally identical to the TL16C750. The
D16750 allows serial transmission in two
modes: UART mode and FIFO mode. In FIFO
mode internal FIFOs are activated allowing 64
bytes (plus 3 bits of error data per byte in the
RCVR FIFO) to be stored in both receive and
transmit directions. D16750 performs serial-to-
parallel conversion on data characters
received from a peripheral device or a
MODEM, and parallel-to-serial conversion on
data characters received from the CPU. The
CPU can read the complete status of the
UART at any time during the functional
operation. Status information reported
includes the type and condition of the transfer
operations being performed by the UART, as
well as any error conditions (parity, overrun,
framing, or break interrupt). D16750 includes
a programmable baud rate generator that is
capable of dividing the timing reference clock
input by divisors of 1 to (216-1), and producing
a 16 × clock for driving the internal transmitter
logic. Provisions are also included to use this
16 × clock to drive the receiver logic. The
D16750 has complete MODEM control
capability, and a processor-interrupt system.
Interrupts can be programmed to the user's
requirements, minimizing the computing
required to handle the communications link.
In the FIFO mode, there is a selectable
autoflow control feature that can significantly
All trademarks mentioned in this document
are trademarks of their respective owners.
reduce software overload and increase
system efficiency by automatically controlling
serial data flow through the RTS output and
the CTS input signals
The separate BAUD CLK line allow to set an
exact transmission speed, while the UART
internal logic is clocked with the CPU
frequency.
Two DMA modes are supported: single
transfer and multi-transfer. These modes
allow UART to interface to higher performance
DMA units, which can interleave their
transfers between CPU cycles or execute
multiple byte transfers.
The configuration capability allows user to
enable or disable during Synthesis process
the Modem Control Logic and FIFO's Control
Logic, change the FIFO size. So in
applications with area limitation and where the
UART works only in 16450 mode, disabling
Modem Control and FIFO's allow to save
about 50% of logic resources.
The core is perfect for applications, where the
UART Core and microcontroller are clocked
by the same clock signal and are implemented
inside the same ASIC or FPGA chip, as well
as for standalone implementation, where
several UARTs are required to be
implemented inside a single chip, and driven
by some off-chip devices. Thanks to universal
interface D16750 core implementation and
verification are very simply, by eliminating a
number of clock trees in complete system.
http://www.DigitalCoreDesign.com
http://www.dcd.pl
Copyright 1999-2007 DCD – Digital Core Design. All Rights Reserved.