Mikroelektronika MIKROE-724 データシート

mikroBasic PRO for dsPIC30/33 and PIC24

MikroElektronika

437

PWMx_Mc_Init

Prototype

sub function PWMx_Mc_Init(dim freq_hz, pair_output_mode, enable_output_x,

clock_prescale_output_postscale as word) as word

Description Initializes the Motor Control PWM module with duty ratio 0. The function calculates timer period, writes

it to the MCU’s PTPER register and returns it as the function result.

Parameters -

freq_hz

: PWM frequency in Hz (refer to device datasheet for correct values in respect with Fosc)

pair_output_mode

: output mode for output pin pairs:

= independent,

= complementary.

pair_output_mode.B0

is equal to 1 then PWM channels PWM1L and PWM1H will be

independent,

pair_output_mode.B1

is equal to 0 then PWM channels PWM2L and PWM2H will be

complementary, ...

pair_output_mode.Bn

is equal to 1 then PWM channels PWM(n+1)L and PWM(n+1)H will be

independent,

pair_output_mode.Bn

is equal to 0 then PWM channels PWM(n+1)L and PWM(n+1)H will be

complementary.

enable_output_x

: bits <7..0> are enabling corresponding PWM channels <

PWM4H

PWM3H

PWM2H

PWM1H

PWM4L

PWM3L

PWM2L

PWM1L

If bit value is equal to

then corresponding PWM channel is disabled (pin is standard I/O).

If bit value is equal to

then corresponding PWM channel is enabled (pin is PWM output).

For detalied explanation consult the “Motor Control PWM Module” section in device datasheet

clock_prescale_output_postscale

: PWM clock prescaler/postscaler settings. Values

<0..3>

and <0..15>

correspond to prescaler/postscaler

<1:1, 1:4, 1:16, 1:64> and <1:1, 1:2,

..., 1:16>

Returns

Calculated timer period.

Requires

The dsPIC30/33 MCU must have the Motor Control PWM module.

Example

‘Initializes the PWM1 module at 5KHz, complementary pin-pair output, output

enabled on pins 4l..1l, no clock prescale and no clock postscale:

dim duty_50 as word

...

duty_50 = PWM1_Mc_Init(5000, 1, $0F, 0)

Notes

- Number of PWM modules per MCU differs from chip to chip. Please, read the appropriate datasheet

before utilizing this library.

- PWM library routines require you to specify the module you want to use. To use the desired PWM

module, simply change the letter

x in the routine prototype for a number from 1 to 2.