//*****************************************************************************
//
// This function prepares the quadrature encoder module for capturing the
// position and speed of the motor.
//
//*****************************************************************************
void
EncoderInit(void)
{
//
// Configure the QEI pins.
//
ROM_GPIOPinTypeQEI(QEI_PHA_PORT, QEI_PHA_PIN);
ROM_GPIOPinTypeQEI(QEI_PHB_PORT, QEI_PHB_PIN);
ROM_GPIOPinTypeQEI(QEI_INDEX_PORT, QEI_INDEX_PIN);
//
// Configure the QEI module.
//
ROM_QEIConfigure(QEI0_BASE,
(QEI_CONFIG_RESET_IDX | QEI_CONFIG_CAPTURE_A |
QEI_CONFIG_QUADRATURE | QEI_CONFIG_NO_SWAP), 0xffffffff);
//
// Initialize the QEI position to zero.
//
ROM_QEIPositionSet(QEI0_BASE, 0);
//
// Enable the QEI module.
//
ROM_QEIEnable(QEI0_BASE);
//
// Configure the encoder input to generate an interrupt on every rising
// edge.
//
ROM_GPIOIntTypeSet(QEI_PHA_PORT, QEI_PHA_PIN, GPIO_RISING_EDGE);
ROM_GPIOPinIntEnable(QEI_PHA_PORT, QEI_PHA_PIN);
ROM_IntEnable(QEI_PHA_INT);
}
char run()
{
unsigned long period = (SysCtlClockGet() / multi2hz(interval)) / 2;
stop();
led(1,0,0);
clear_buf();
if (mode == MODE_INTERVAL)
{
ROM_IntEnable(INT_TIMER0A);
ROM_TimerLoadSet(TIMER0_BASE, TIMER_A, period - 1);
ROM_TimerIntClear(TIMER0_BASE, TIMER_TIMA_TIMEOUT);
ROM_TimerIntEnable(TIMER0_BASE, TIMER_TIMA_TIMEOUT);
if (trigger == TRIGGER_IMMEDIATE)
{
ROM_TimerEnable(TIMER0_BASE, TIMER_A);
}
else if (trigger == TRIGGER_PIN_RISING)
{
ROM_GPIOIntTypeSet(GPIO_PORTB_BASE, trigger_pins, GPIO_RISING_EDGE);
ROM_GPIOPinIntClear(GPIO_PORTB_BASE, 0xff);
ROM_GPIOPinIntEnable(GPIO_PORTB_BASE, trigger_pins);
ROM_IntEnable(INT_GPIOB);
}
else if (trigger == TRIGGER_PIN_FALLING)
{
ROM_GPIOIntTypeSet(GPIO_PORTB_BASE, trigger_pins, GPIO_FALLING_EDGE);
ROM_GPIOPinIntClear(GPIO_PORTB_BASE, 0xff);
ROM_GPIOPinIntEnable(GPIO_PORTB_BASE, trigger_pins);
ROM_IntEnable(INT_GPIOB);
}
else if (trigger == TRIGGER_PIN_BOTH)
{
ROM_GPIOIntTypeSet(GPIO_PORTB_BASE, 1, GPIO_BOTH_EDGES);
ROM_GPIOPinIntClear(GPIO_PORTB_BASE, 0xff);
ROM_GPIOPinIntEnable(GPIO_PORTB_BASE, trigger_pins);
ROM_IntEnable(INT_GPIOB);
}
}
else if (mode == MODE_EVENT)
{
if (trigger == TRIGGER_PIN_FALLING)
{
ROM_GPIOIntTypeSet(GPIO_PORTB_BASE, trigger_pins, GPIO_FALLING_EDGE);
ROM_GPIOPinIntClear(GPIO_PORTB_BASE, 0xff);
ROM_GPIOPinIntEnable(GPIO_PORTB_BASE, trigger_pins);
ROM_IntEnable(INT_GPIOB);
}
else if (trigger == TRIGGER_PIN_RISING)
{
ROM_GPIOIntTypeSet(GPIO_PORTB_BASE, trigger_pins, GPIO_RISING_EDGE);
ROM_GPIOPinIntClear(GPIO_PORTB_BASE, 0xff);
ROM_GPIOPinIntEnable(GPIO_PORTB_BASE, trigger_pins);
ROM_IntEnable(INT_GPIOB);
}
else if (trigger == TRIGGER_PIN_BOTH)
{
ROM_GPIOIntTypeSet(GPIO_PORTB_BASE, trigger_pins, GPIO_BOTH_EDGES);
ROM_GPIOPinIntClear(GPIO_PORTB_BASE, 0xff);
ROM_GPIOPinIntEnable(GPIO_PORTB_BASE, trigger_pins);
ROM_IntEnable(INT_GPIOB);
}
HWREG(NVIC_ST_CURRENT) = 0;
}
ROM_IntMasterEnable();
sampling = SAMPLING_ON;
return STATE_GET_COMMAND;
}
//*****************************************************************************
//
// Toggle the JTAG pins between JTAG and GPIO mode with a push button selecting
// between the two.
//
//*****************************************************************************
int
main(void)
{
unsigned long ulMode;
//
// Set the clocking to run directly from the crystal.
//
ROM_SysCtlClockSet(SYSCTL_SYSDIV_1 | SYSCTL_USE_OSC | SYSCTL_OSC_MAIN |
SYSCTL_XTAL_16MHZ);
//
// Enable the peripherals used by this application.
//
ROM_SysCtlPeripheralEnable(SYSCTL_PERIPH_GPIOA);
ROM_SysCtlPeripheralEnable(SYSCTL_PERIPH_GPIOB);
ROM_SysCtlPeripheralEnable(SYSCTL_PERIPH_GPIOC);
ROM_SysCtlPeripheralEnable(SYSCTL_PERIPH_GPIOD);
//
// Configure the push button as an input and enable the pin to interrupt on
// the falling edge (i.e. when the push button is pressed).
//
ROM_GPIOPinTypeGPIOInput(GPIO_PORTB_BASE, GPIO_PIN_4);
ROM_GPIOPadConfigSet(GPIO_PORTB_BASE, GPIO_PIN_4, GPIO_STRENGTH_2MA,
GPIO_PIN_TYPE_STD_WPU);
ROM_GPIOIntTypeSet(GPIO_PORTB_BASE, GPIO_PIN_4, GPIO_FALLING_EDGE);
ROM_GPIOPinIntEnable(GPIO_PORTB_BASE, GPIO_PIN_4);
ROM_IntEnable(INT_GPIOB);
//
// Configure the LED as an output and turn it on.
//
ROM_GPIOPinTypeGPIOOutput(GPIO_PORTD_BASE, GPIO_PIN_0);
ROM_GPIOPinWrite(GPIO_PORTD_BASE, GPIO_PIN_0, GPIO_PIN_0);
//
// Set the global and local indicator of pin mode to zero, meaning JTAG.
//
g_ulMode = 0;
ulMode = 0;
//
// Initialize the UART.
//
GPIOPinConfigure(GPIO_PA0_U0RX);
GPIOPinConfigure(GPIO_PA1_U0TX);
ROM_GPIOPinTypeUART(GPIO_PORTA_BASE, GPIO_PIN_0 | GPIO_PIN_1);
UARTStdioInit(0);
UARTprintf("\033[2JGPIO <-> JTAG\n");
//
// Indicate that the pins start out as JTAG.
//
UARTprintf("Pins are JTAG\n");
//
// Loop forever. This loop simply exists to display on the UART the
// current state of PC0-3; the handling of changing the JTAG pins to and
// from GPIO mode is done in GPIO Interrupt Handler.
//
while(1)
{
//
// Wait until the pin mode changes.
//
while(g_ulMode == ulMode)
{
}
//
// Save the new mode locally so that a subsequent pin mode change can
// be detected.
//
ulMode = g_ulMode;
//
// See what the new pin mode was changed to.
//
if(ulMode == 0)
{
//
// Indicate that PC0-3 are currently JTAG pins.
//
UARTprintf("Pins are JTAG\n");
}
else
{
//
// Indicate that PC0-3 are currently GPIO pins.
//
UARTprintf("Pins are GPIO\n");
}
}
}
