Philips Semiconductors

Product data sheet

PCA9533

2004 Oct 01

10

Programming example

The following example will show how to set LED0 and LED1 off. It

will set LED2 to blink at 1 Hz, 50 % duty cycle. LED3 will be set to

be dimmed at 25 % of their maximum brightness

(duty cycle = 25 %). PCA9533/01 is used in this example.

Table 1.

Start

S

PCA9533 address

C4h

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 PWM1 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 on, LED1 off, LED2 set to blink at PSC0,

PWM0, LED3 set to blink at PCS1, PWM1

E1h

Stop

P