ZUSBOPTSC01ZACG datasheet(93/282 Pages) ZILOG

93 / 282 page

PS022827-1212

P R E L I M I N A R Y

Operation

Z8 Encore! XP® F082A Series

Product Specification

PWM SINGLE OUTPUT Mode

In PWM SINGLE OUTPUT Mode, the timer outputs a Pulse-Width Modulator (PWM)

output signal through a GPIO port pin. The timer input is the system clock. The timer first

counts up to the 16-bit PWM match value stored in the Timer PWM High and Low Byte

registers. When the timer count value matches the PWM value, the Timer Output toggles.

The timer continues counting until it reaches the reload value stored in the Timer Reload

High and Low Byte registers. Upon reaching the reload value, the timer generates an inter-

rupt, the count value in the Timer High and Low Byte registers is reset to 0001H and

counting resumes.

If the TPOL bit in the Timer Control Register is set to 1, the Timer Output signal begins as

a High (1) and transitions to a Low (0) when the timer value matches the PWM value. The

Timer Output signal returns to a High (1) after the timer reaches the reload value and is

reset to 0001H.

If the TPOL bit in the Timer Control Register is set to 0, the Timer Output signal begins as

a Low (0) and transitions to a High (1) when the timer value matches the PWM value. The

Timer Output signal returns to a Low (0) after the timer reaches the reload value and is

reset to 0001H.

Observe the following steps for configuring a timer for PWM SINGLE OUTPUT Mode

and initiating the PWM operation:

1. Write to the Timer Control Register to:

–

Disable the timer

–

Configure the timer for PWM SINGLE OUTPUT Mode

–

Set the prescale value

–

Set the initial logic level (High or Low) and PWM High/Low transition for the

Timer Output alternate function



2. Write to the Timer High and Low Byte registers to set the starting count value (typi-

cally 0001H). This only affects the first pass in PWM mode. After the first timer reset

in PWM mode, counting always begins at the reset value of 0001H.

3. Write to the PWM High and Low Byte registers to set the PWM value.

4. Write to the Timer Reload High and Low Byte registers to set the reload value (PWM

period). The reload value must be greater than the PWM value.

5. If appropriate, enable the timer interrupt and set the timer interrupt priority by writing

to the relevant interrupt registers.

6. Configure the associated GPIO port pin for the Timer Output alternate function.

7. Write to the Timer Control Register to enable the timer and initiate counting.



ZUSBOPTSC01ZACG 数据表(PDF) 93 Page - Zilog, Inc.

ZUSBOPTSC01ZACG 数据表(HTML) 93 Page - Zilog, Inc.

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 ...More

数据表下载