Make the specified Pin high. Pin is automatically made an output. Pin may be a constant, 0-15, or a variable that contains a number 0-15 (e.g. B0) or a pin name (e.g. PORTA.0).
HIGH 0 ' Make Pin0 an output and set it high (~5 volts) HIGH PORTA.0 ' Make PORTA, pin 0 an output and set it high (~5 volts) led var PORTB.0 ' Define LED pin HIGH led ' Make LED pin an output and set it high (~5 volts)
Alternatively, if the pin is already an output, a much quicker and shorter way (from a generated code standpoint) to set it high would be:
PORTB.0 = 1 ' Set PORTB pin 0 high
Outputs a pulse width modulated pulse train using PWM hardware available on some PICmicro MCUs. It can run continuously in the background while the program is executing other instructions.
Channel specifies which hardware PWM channel to use. Some devices have 1, 2 or 3 PWM channels. On devices with 2 channels, the Frequency must be the same on both channels.
Channel specifies which hardware PWM channel to use. Some devices have 1, 2 or 3 PWM Channels. The Microchip data sheet for the particular device shows the fixed hardware pin for each Channel. For example, for a PIC16F877, Channel 1 is CCP1 which is pin PORTC.2. Channel 2 is CCP2 which is pin PORTC.1.
Some devices, such as the PIC18C452, have alternate pins that may be used for HPWM. The following DEFINEs allow using these pins:
DEFINE CCP1_REG PORTC ‘ Hpwm 1 pin port DEFINE CCP1_BIT 2 ‘ Hpwm 1 pin bit DEFINE CCP2_REG PORTC ‘ Hpwm 2 pin port DEFINE CCP2_BIT 1 ‘ Hpwm 2 pin bit
Dutycycle specifies the on/off (high/low) ratio of the signal. It ranges from 0 to 255, where 0 is off (low all the time) and 255 is on (high) all the time. A value of 127 gives a 50% duty cycle (square wave).
Frequency is the desired frequency of the PWM signal. Not all frequencies are available at all oscillator settings. The highest frequency at any oscillator speed is 32767Hz. The lowest usable HPWM Frequency at each oscillator setting is shown in the following table:
|OSC||14-bit core and 18Cxxx||17Cxxx|
The following DEFINEs specify which timer, 1 or 2, to use with PWM channel 2 and PWM channel 3 for the PIC17C7xx devices. The default is timer 1 if no DEFINE is specified.
DEFINE HPWM2_TIMER 1 'Hpwm 2 timer select DEFINE HPWM3_TIMER 1 'Hpwm 3 timer select HPWM 1,127,1000 ' Send a 50% duty cycle PWM signal at 1kHz HPWM 1,64,2000 ' Send a 25% duty cycle PWM signal at 2kHz