Motorola MCF5281 用户手册
MOTOROLA
Chapter 23. UART Modules
23-1
Chapter 23
UART Modules
This chapter describes the use of the universal asynchronous receiver/transmitters (UARTs)
implemented on the MCF5282 and includes programming examples.
implemented on the MCF5282 and includes programming examples.
NOTE
The designation “n” is used throughout this section to refer to
registers or signals associated with one of the three identical
UART modules: UART0, UART1, or UART2.
registers or signals associated with one of the three identical
UART modules: UART0, UART1, or UART2.
23.1 Overview
The MCF5282 contains three independent UARTs. Each UART can be clocked by the
system clock, eliminating the need for an external UART clock. As Figure 23-1 shows,
each UART module interfaces directly to the CPU and consists of the following:
system clock, eliminating the need for an external UART clock. As Figure 23-1 shows,
each UART module interfaces directly to the CPU and consists of the following:
• Serial communication channel
• Programmable clock generation
• Internal channel control logic
• Interrupt control logic
• Programmable clock generation
• Internal channel control logic
• Interrupt control logic
Figure 23-1. Simplified Block Diagram
NOTE
UART0 can be clocked by the DTIN0 pin. UART1 can be
clocked by the DTIN1 pin, and UART2 can be clocked by
DTIN2.
clocked by the DTIN1 pin, and UART2 can be clocked by
DTIN2.
Serial
Interrupt Control
Logic
UCTS
URTS
URXD
UTXD
URTS
URXD
UTXD
or
External clock (DTINn)
External clock (DTINn)
Internal Channel
Control Logic
Programmable
Clock
Communications
Channel
Generation
System Control
Module (SCM)
Interrupt
Controller
UART
System Clock