mcf5407 Freescale Semiconductor, Inc, mcf5407 Datasheet - Page 367

• Manufacturer Part Number: mcf5407
• Description: Mcf5407 Coldfire Integrated Microprocessor User
• Manufacturer: Freescale Semiconductor, Inc

Let baud rate = 9600; the divider can be calculated as follows:
Therefore UDUn = 0x00 and UDLn = 0xB0.
14.5.1.2.2 External Clock
An external source clock (TIN) can be used as is or divided by 16.
14.5.2 Transmitter and Receiver Operating Modes
Figure 14-29 is a functional block diagram of the transmitter and receiver showing the
command and operating registers, which are described generally in the following sections
and described in detail in Section 14.3, “Register Descriptions.”
Transmitter Buffer
(2 Registers)
(UTB0)
UART
Figure 14-29. Transmitter and Receiver Functional Diagram
UART Receive
Buffer (URB0)
(4 Registers)
Divider
Receiver Holding Register 1
UART Command Register (UCR0)
UART Mode Register 1 (UMR1)
UART Mode Register 2 (UMR2)
UART Status Register (USR0)
Transmitter Holding Register
Baudrate
Receiver Holding Register 2
Transmitter Shift Register
Chapter 14. UART Modules
=
---------------------------- -
[
Receiver Holding Register 3
Baudrate
32 9600
54MHz
×
UART0
Receiver Shift Register
=
Externalclockfrequency
-------------------------------------------------------------------- -
]
=
=
----------------------------------- -
[
32 divider
176 decimal
54MHz
×
16or1
(
]
)
=
0x00B0
R/W
R/W
R
W
W
R
FIFO (32-byte
FIFOs on
UART1)
Operation
External
Interface
14-25
RXD
TXD