trapmod.c

Luminary Micro BLDC motor control software

//*****************************************************************************
//
// trapmod.c - Trapezoid modulation routine.
//
// Copyright (c) 2008 Luminary Micro, Inc.  All rights reserved.
// 
// Software License Agreement
// 
// Luminary Micro, Inc. (LMI) is supplying this software for use solely and
// exclusively on LMI's microcontroller products.
// 
// The software is owned by LMI and/or its suppliers, and is protected under
// applicable copyright laws.  All rights are reserved.  You may not combine
// this software with "viral" open-source software in order to form a larger
// program.  Any use in violation of the foregoing restrictions may subject
// the user to criminal sanctions under applicable laws, as well as to civil
// liability for the breach of the terms and conditions of this license.
// 
// THIS SOFTWARE IS PROVIDED "AS IS".  NO WARRANTIES, WHETHER EXPRESS, IMPLIED
// OR STATUTORY, INCLUDING, BUT NOT LIMITED TO, IMPLIED WARRANTIES OF
// MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE APPLY TO THIS SOFTWARE.
// LMI SHALL NOT, IN ANY CIRCUMSTANCES, BE LIABLE FOR SPECIAL, INCIDENTAL, OR
// CONSEQUENTIAL DAMAGES, FOR ANY REASON WHATSOEVER.
// 
// This is part of revision 716 of the BLDC motor application.
//
//*****************************************************************************

#include "../../DriverLib/hw_types.h"
#include "trapmod.h"
#include "adc_ctrl.h"
#include "main.h"
#include "ui.h"
#include "pins.h"
#include "pwm_ctrl.h"

//*****************************************************************************
//
//! \page trapmod_intro Introduction
//!
//! The code for producing trapezoid modulated waveforms is contained in
//! <tt>trapmod.c</tt>, with <tt>trapmod.h</tt> containing the definition for
//! the function exported to the remainder of the application.
//
//*****************************************************************************

//*****************************************************************************
//
//! \defgroup trapmod_api Definitions
//! @{
//
//*****************************************************************************

//*****************************************************************************
//
//! PWM Phase A (High + Low).
//
//*****************************************************************************
#define PHASE_A         (PWM_PHASEA_HIGH | PWM_PHASEA_LOW)

//*****************************************************************************
//
//! PWM Phase B (High + Low).
//
//*****************************************************************************
#define PHASE_B         (PWM_PHASEB_HIGH | PWM_PHASEB_LOW)

//*****************************************************************************
//
//! PWM Phase C (High + Low).
//
//*****************************************************************************
#define PHASE_C         (PWM_PHASEC_HIGH | PWM_PHASEC_LOW)

//*****************************************************************************
//
//! Mapping from Hall States to Phase Drive states.
//!
//! This array maps the hall state value to the set of PWM
//! signals that should be driving at that time.
//!
//! \verbatim
//!     ---------+---+---+---+---+---+---+
//!     Phase A  | - | - | Z | + | + | Z |
//!     Phase B  | + | Z | - | - | Z | + |
//!     Phase C  | Z | + | + | Z | - | - |
//!     ---------+---+---+---+---+---+---+
//!     Hall A   | 1 | 1 | 1 | 0 | 0 | 0 |
//!     Hall B   | 0 | 0 | 1 | 1 | 1 | 0 |
//!     Hall C   | 1 | 0 | 0 | 0 | 1 | 1 |
//!     ---------+---+---+---+---+---+---+
//! \endverbatim
//
//*****************************************************************************
static const unsigned long g_ulHallToPhase120[8] =
{
    0,
    PWM_PHASEC_HIGH | PWM_PHASEA_LOW,
    PWM_PHASEA_HIGH | PWM_PHASEB_LOW,
    PWM_PHASEC_HIGH | PWM_PHASEB_LOW,
    PWM_PHASEB_HIGH | PWM_PHASEC_LOW,
    PWM_PHASEB_HIGH | PWM_PHASEA_LOW,
    PWM_PHASEA_HIGH | PWM_PHASEC_LOW,
    0
};

//*****************************************************************************
//
//! Controls trapezoid modulated waveforms.
//!
//! \param ulHall is the current Hall state value for the motor.  This
//! value may be read directly from the Hall sensors, if installed, or
//! derived from the Back EMF or Linear Hall sensor readings.
//!
//! This function will control the PWM generator channels based on the changes
//! in the Hall Effect sensor value.
//!
//! \return None.
//
//*****************************************************************************
void
TrapModulate(unsigned long ulHall)
{
    unsigned long ulEnable;

    //
    // If the motor is not running, there is nothing to do.
    //
    if(!MainIsRunning())
    {
        return;
    }

    //
    // Convert the Hall value into a bit-mapped phase enable value.
    //
    ulEnable = g_ulHallToPhase120[ulHall];

    //
    // If running in reverse, invert the PWM phases.
    //
    if(MainIsReverse())
    {
        if(ulEnable & PHASE_A)
        {
            ulEnable ^= PHASE_A;
        }
        if(ulEnable & PHASE_B)
        {
            ulEnable ^= PHASE_B;
        }
        if(ulEnable & PHASE_C)
        {
            ulEnable ^= PHASE_C;
        }
    }

    //
    // Switch the PWM outputs.
    //
    PWMOutputTrapezoid(ulEnable);
}

//*****************************************************************************
//
// Close the Doxygen group.
//! @}
//
//*****************************************************************************