EP80579 Datasheet, PDF (1172/1916 Pages) Intel Corporation – Intel® EP80579 Integrated Processor Product Line

Intel^® EP80579 Integrated Processor
any time during the functional operation. Available status information includes the type
and condition of the transfer operations being performed by the UART and any error
conditions (parity, overrun, framing, or break interrupt).
The serial port can operate in either FIFO or non-FIFO mode. In FIFO mode, a 16-byte
transmit FIFO holds data from the processor to be transmitted on the serial link and a
16-byte Receive FIFO buffers data from the serial link until read by the processor.
Each UART includes a programmable baud rate generator which is capable of dividing
the baud clock input by divisors of one to (2 ¹⁶ -1) and producing a 16X clock to drive
the internal transmitter and receiver logic. Each UART 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. Each UART can operate in a polled or an interrupt driven environment as
configured by software.
The baud rate generator input is a function of the UART_CLK and a configurable
predivide of 1, 8, or 26. See also SIW Configuration (address 29h) in Section 33.8.3.1,
“Global Control/Configuration Registers [00h - 2Fh]” on page 1208. The output of the
baud rate generator is 16 times the baud rate.
Table 33-4. UART Clock Divider Support
Clock Frequency
Predivide Value
Generator Frequency
14.7456 MHz
8
1.8432 MHz
48.0 MHz
26
1.8462 MHz
Table 33-5. Baud Rate Example
Desired Baud Rate
300
1200
2400
4800
9600
19200
38400
56000
115200
Divisor
384
96
48
24
12
6
3
2
1
% error @ 1.8432
2.8
% error @
1.8462*
0.16
0.16
0.16
0.16
0.16
0.16
0.16
3
0.16
33.5.1
UART Feature List
• Functionally compatible with National Semiconductor's* PC16550D.
• Adds or deletes standard asynchronous communications bits (start, stop, and
parity) to or from the serial data.
• Independently controlled transmit, receive, line status and data set interrupts.
• Programmable baud rate generator allows division of clock by 1 to (216 -1) and
generates an internal 16X clock.
• Modem control functions (CTS#, RTS#, DSR#, DTR#, RI#, and DCD#).
Intel^® EP80579 Integrated Processor Product Line Datasheet
1172
August 2009
Order Number: 320066-003US