Philips Semiconductors

Preliminary data

PCA9530

2002 Dec 12

9

Programming example

The following example will show how to set LED0 to blink at 1 Hz at

a 50% duty cycle. LED1 will be set to be dimmed at 25% of their

maximum brightness (duty cycle = 25%).

Table 1.

Start

S

PCA9530 address with A0 = low

COh

PSC0 subaddress + auto-increment

11h

Set prescaler PSC0 to achieve a period of 1 second:

Blink period

+ 1 + PSC0 ) 1

152

PSC0 = 151

97h

Set PWM0 duty cycle to 50%:

PWM0

256

+ 0.5

PWM0 = 128

80h

Set prescaler PCS1 to dim at maximum frequency.

Blink period

+ maximum

PSC1 = 0

00h

Set PWM1 output duty cycle to 25%:

PWM1

256

+ 0.25

PWM1 = 64

40h

Set LED0 to PWM0 and set LED1 to blink at PWM1

OEh

Stop

P