Address 0x05 (PWM1)

Bit #

76543210

Default value

10000000

PWM1 register determines the duty cycle of DIM1. The LED outputs are LOW (LED on) when the count is less than the value in PWM1 and HIGH (LED off) when

it is greater. If PWM1 is programmed with 0x00, LED output is always HIGH (LED off).

The duty cycle of DIM1 is: PWM1/256

Default value is 50% duty cycle.

BINARY FORMAT FOR SELECTOR REGISTERS — ADDRESS 0x06 to 0x07

Address 0x06 (LS0)

Bit #

76543210

Default value

00000000

B1

B0

B1

B0

B1

B0

B1

B0

LED3

LED2

LED1

LED0

Address 0x07 (LS1)

Bit #

76543210

Default value

00000000

B1

B0

B1

B0

B1

B0

B1

B0

LED7

LED6

LED5

LED4

LED States With Respect To Values in "B1" and "B0"

B1

B0

Function

0

0

Output Hi-Z

(LED off)

0

1

Output LOW

(LED on)

1

0

Output dims

(DIM0 rate)

1

1

Output dims

(DIM1 rate)

Programming Example:

Dim LEDs 0 to 7 at 1 Hz at 25% duty cycle

Step 1: Set PSC0 to achieve DIM0 of 1s

Step 2: Set PWM0 duty cycle to 25%

Step 3: Set PSC1 to achieve DIM1 of 0.2s

Step 4: Set LEDs 0 to 7 to point to DIM0

Step

Description

Register Name

Set to (Hex)

1

Set DIM0 = 1s

1 = (PSC0 + 1)/160

PSC0 = 159

PSC0

0x09F

2

Set duty cycle to 25%

Duty Cycle = PWM0/256

PWM0 = 64

PWM0

0x40

3

Set DIM1 = 0.2s

0.2 = (PSC1 + 1)/160

PSC1 = 31

PSC1

0x1F

4

LEDs0to7

Output = DIM0

LS0, LS1

LS0 = 0xAA

LS1 = 0xAA

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