Fujitsu F202RA, MB89202 manual Program Example for Uart, Program specifications

CHAPTER 13 UART

13.7Program Example for UART

This section provides program example for UART.

■Program Example for UART

●Program specifications

•Serial data transfer is implemented using the UART communication functions.

•The P30/UCK/SCK, P31/UO/SO, and P32/UI/SI pins are used for communication.

•The transfer rate is set to 300 bps using the internal baud rate generator.

•13H is transmitted from the UO pin, and data is received by interrupts.

•The baud rate is the oscillation frequency (FCH = 12.5 MHz) at the maximum gear speed (1 instruction cycle = 4/FCH). The clock divider is 2.5. (1/375 bps = 8320 tINST)

●Coding example

PDR3	EQU	000CH	;	Port data register address
DDR3	EQU	000DH	;	Port direction register address
SSEL	EQU	003BH	;	Serial selection register address
SMC	EQU	0028H	;	Serial mode control register address
SRC	EQU	0029H	;	Serial rate control register address
SSD	EQU	002AH	;	Serial status and data register address
SIDR	EQU	002BH	;	Serial input data register address
SODR	EQU	002BH	;	Serial output data register address
UPC	EQU	002CH	;	Clock divider selection register address
ILR2	EQU	007CH	;	Interrupt level setting register address
INT_V	DSEG	ABS	;	[DATA SEGMENT]
	ORG	0FFEEH
IRQ6	DW	WARI2	;	Reception interrupt vector setting
IRQ5	DW	WARI1	;	Transmission interrupt vector setting
INT_V	ENDS
;--------------------		Main program---------------------------------------------------------------------------
	CSEG		;	[CODE SEGMENT]
			; The stack pointer (SP) and related components have to be
				initialized.
	:
	CLRI		;	Disable interrupts.
	MOV	ILR2,#11101011B	;	Set an interrupt level (level 1).
	MOV	UPC,#11111010B	;	Allow operation with the clock whose frequency is divided
				by 2.5.
	MOV	SSEL,#00000000B	;	Select UART.
	MOV	DDR3,#00000000B	;	Set the UI pin as the input pin.
	MOV	SMC,#01011011B	;	Set non-parity, the number of stop bits 1, and operating

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