1.10.13 1.11.14 1.12.14 1.13.13 Motor Control Pulse-Width Modulation (MCPWM)
The PIC32MK GP/MC Family of devices support a dedicated Motor Control Pulse-Width Modulation (PWM) module with up to 12 outputs. The Motor Control PWM module consists of the following major features:
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Two master time base modules with special event triggers
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PWM module input clock prescaler
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Two synchronization inputs
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Two synchronization outputs
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Eight PWM generators with complimentary output pairs
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Four additional PWM generators with single ended outputs
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Period, duty cycle, phase shift and dead time minimum resolution of 1 / FSYSCLK in Edge-Aligned mode and 2 / FSYSCLK minimum resolution in Center-Aligned mode
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Cycle by cycle fault recovery and latched fault modes
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PWM time-base capture upon current limit
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Nine fault input pins are available for faults and current limits
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Programmable analog-to-digital trigger with interrupt for each PWM pair
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Complementary PWM outputs
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Push-Pull PWM outputs
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Redundant PWM outputs
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Edge-Aligned PWM mode
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Center-Aligned PWM mode
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Variable Phase PWM mode
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Multi-Phase PWM mode
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Fixed-Off Time PWM mode
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Current Limit PWM mode
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Current Reset PWM mode
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PWMxH and PWMxL output override control
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PWMxH and PWMxL output pin swapping
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Chopping mode (also known as Gated mode)
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Dead time insertion
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Dead time compensation
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Enhanced Leading-Edge Blanking (LEB)
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15 mA PWM pin output drive
Using The Library
This example shows how to configure the MCPWM to generate PWM signals whose duty and period can be configured independently.
/* Duty cycle increment value */ #define DUTY_INCREMENT (10U) /* Save PWM period */ uint16_t period; /* This function is called after PWM0 counter event */ void PWM_PeriodHandler(uint32_t status, uintptr_t context) { /* duty cycle values */ static uint16_t duty0 = 0U; static uint16_t duty1 = 1000U; static uint16_t duty2 = 2000U; MCPWM_ChannelPrimaryDutySet(MCPWM_CH_1, duty0); MCPWM_ChannelPrimaryDutySet(MCPWM_CH_2, duty1); MCPWM_ChannelPrimaryDutySet(MCPWM_CH_3, duty2); /* Increment duty cycle values */ duty0 += DUTY_INCREMENT; duty1 += DUTY_INCREMENT; duty2 += DUTY_INCREMENT; if (duty0 > period) duty0 = 0U; if (duty1 > period) duty1 = 0U; if (duty2 > period) duty2 = 0U; } int main ( void ) { /* Initialize all modules */ SYS_Initialize ( NULL ); /* Register callback function for Channel 0 counter event */ MCPWM_CallbackRegister(MCPWM_CH_1, PWM_PeriodHandler, (uintptr_t)NULL); /* Read the period */ period = MCPWM_PrimaryPeriodGet(); /* Start all synchronous channels by starting channel 0*/ MCPWM_Start(); while ( true ) { /* Maintain state machines of all polled MPLAB Harmony modules. */ SYS_Tasks ( ); } /* Execution should not come here during normal operation */ return ( EXIT_FAILURE ); }
Library Interface
Peripheral library provides the following interfaces:
Functions
Name | Description |
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MCPWM_Initialize | Initializes given instance of MCPWM peripheral |
MCPWM_Start | Starts the MCPWM module |
MCPWM_Stop | Stops the given MCPWM module |
MCPWM_PrimaryPeriodSet | Sets the period value of the primary time base |
MCPWM_SecondaryPeriodSet | Sets the period value of the secondary time base |
MCPWM_PrimaryPeriodGet | Reads the period value of primary time base generator |
MCPWM_SecondaryPeriodGet | Reads the period value of secondary time base generator |
MCPWM_ChannelPrimaryDutySet | Writes the primary duty cycle value of given MCPWM channel |
MCPWM_ChannelSecondaryDutySet | Writes the secondary duty cycle value of given MCPWM channel |
MCPWM_ChannelDeadTimeSet | Writes dead time values of given MCPWM channel |
MCPWM_ChannelPrimaryTriggerSet | Writes the primary trigger compare value to trigger ADC conversion |
MCPWM_ChannelSecondaryTriggerSet | Writes the secondary trigger compare value to trigger ADC conversion |
MCPWM_PrimaryEventCallbackRegister | Registers the function to be called from interrupt |
MCPWM_SecondaryEventCallbackRegister | Registers the function to be called from interrupt |
MCPWM_CallbackRegister | Registers the function to be called from interrupt |
MCPWM_ChannelPinsOverrideEnable | Enables PWM output pins override function |
MCPWM_ChannelPinsOverrideDisable | Disables PWM output pins override function |
MCPWM_ChannelPinsOwnershipEnable | Sets the PWM output pins ownership to PWM generator |
MCPWM_ChannelPinsOwnershipDisable | Sets the PWM output pins ownership to GPIO |
Data types and constants
Name | Type | Description |
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MCPWM_CH_CALLBACK | Typedef | Defines the data type and function signature for the MCPWM peripheral callback function |
MCPWM_CALLBACK | Typedef | Defines the data type and function signature for the MCPWM peripheral callback function for primary event and secondary event |
MCPWM_CH_NUM | Enum | Identifies MCPWM channel number in a MCPWM peripheral |
MCPWM_CH_STATUS | Enum | Identifies MCPWM channel event status |