Samsung S3C84E5 Programming TIP To generate a one pulse signal through P4.3, TBDATAH,# Set 40 μs

8-BIT TIMER A/B S3C84E5/C84E9/P84E9

FPROGRAMMING TIP — To generate a one pulse signal through P4.3

This example sets Timer B to the one shot mode, sets the oscillation frequency as the Timer B clock source, and TBDATAH and TBDATAL to make a 40μs width pulse. The program parameters are:

40 μs

—Timer B is used in one shot mode

—Oscillation frequency is 4 MHz (fx=1/4 clock = 1 μs)

—TBDATAH = 40 μs / 1 μs = 40, TBDATAL = 1

—Set P4.3 to TBPWM mode

ORG 0100H ; Reset address

START DI

•
•
•
LD	TBDATAH,# (40-1)	;	Set 40 μs
LD	TBDATAL,# 1	;	Set any value except 00H
LD	TBCON,#00010001B	;	Clock Source ← fxx/4

;Disable Timer B interrupt.

;Select one shot mode for Timer B.

;Stop Timer B operation.

;Set Timer B output flip-flop (T-FF) high

LD	P4CONL, #03H	;	Set P4.3 to TBPWM mode.
•
•
PULSE_OUT:LD	TBCON,#00000101B	;	Start Timer B operation
		;	to make the pulse at this point.
•		;	After the instruction is executed, 0.75 μs is required
•		;	before the falling edge of the pulse starts.
•

11-10