From c3e4c9a25c2910d2d66d52215b3406b13d5b23d5 Mon Sep 17 00:00:00 2001 From: Yuval Adam Date: Sun, 29 Jun 2014 12:34:32 +0300 Subject: Add more board models --- boards/ek-lm4f232/drivers/buttons.c | 186 ++++++++++++++++++++++++++++++++++++ 1 file changed, 186 insertions(+) create mode 100644 boards/ek-lm4f232/drivers/buttons.c (limited to 'boards/ek-lm4f232/drivers/buttons.c') diff --git a/boards/ek-lm4f232/drivers/buttons.c b/boards/ek-lm4f232/drivers/buttons.c new file mode 100644 index 0000000..9dc9ce9 --- /dev/null +++ b/boards/ek-lm4f232/drivers/buttons.c @@ -0,0 +1,186 @@ +//***************************************************************************** +// +// buttons.c - Evaluation board driver for push buttons. +// +// Copyright (c) 2011-2014 Texas Instruments Incorporated. All rights reserved. +// Software License Agreement +// +// Texas Instruments (TI) is supplying this software for use solely and +// exclusively on TI's microcontroller products. The software is owned by +// TI and/or its suppliers, and is protected under applicable copyright +// laws. You may not combine this software with "viral" open-source +// software in order to form a larger program. +// +// THIS SOFTWARE IS PROVIDED "AS IS" AND WITH ALL FAULTS. +// 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. TI SHALL NOT, UNDER ANY +// CIRCUMSTANCES, BE LIABLE FOR SPECIAL, INCIDENTAL, OR CONSEQUENTIAL +// DAMAGES, FOR ANY REASON WHATSOEVER. +// +// This is part of revision 2.1.0.12573 of the EK-LM4F232 Firmware Package. +// +//***************************************************************************** + +#include +#include +#include +#include "driverlib/gpio.h" +#include "driverlib/pin_map.h" +#include "driverlib/rom_map.h" +#include "driverlib/sysctl.h" +#include "inc/hw_types.h" +#include "inc/hw_memmap.h" +#include "buttons.h" + +//***************************************************************************** +// +//! \addtogroup buttons_api +//! @{ +// +//***************************************************************************** + +//***************************************************************************** +// +// Holds the current, debounced state of each button. A 0 in a bit indicates +// that that button is currently pressed, otherwise it is released. +// We assume that we start with all the buttons released (though if one is +// pressed when the application starts, this will be detected). +// +//***************************************************************************** +static uint8_t g_ui8ButtonStates = ALL_BUTTONS; + +//***************************************************************************** +// +//! Polls the current state of the buttons and determines which have changed. +//! +//! \param pui8Delta points to a character that will be written to indicate +//! which button states changed since the last time this function was called. +//! This value is derived from the debounced state of the buttons. +//! \param pui8RawState points to a location where the raw button state will +//! be stored. +//! +//! This function should be called periodically by the application to poll the +//! pushbuttons. It determines both the current debounced state of the buttons +//! and also which buttons have changed state since the last time the function +//! was called. +//! +//! In order for button debouncing to work properly, this function should be +//! caled at a regular interval, even if the state of the buttons is not needed +//! that often. +//! +//! If button debouncing is not required, the the caller can pass a pointer +//! for the \e pui8RawState parameter in order to get the raw state of the +//! buttons. The value returned in \e pui8RawState will be a bit mask where +//! a 1 indicates the buttons is pressed. +//! +//! \return Returns the current debounced state of the buttons where a 1 in the +//! button ID's position indicates that the button is pressed and a 0 +//! indicates that it is released. +// +//***************************************************************************** +uint8_t +ButtonsPoll(uint8_t *pui8Delta, uint8_t *pui8RawState) +{ + uint32_t ui32Delta; + uint32_t ui32Data; + static uint8_t ui8SwitchClockA = 0; + static uint8_t ui8SwitchClockB = 0; + + // + // Read the raw state of the push buttons. Save the raw state + // (inverting the bit sense) if the caller supplied storage for the + // raw value. + // + ui32Data = (MAP_GPIOPinRead(BUTTONS_GPIO_BASE, ALL_BUTTONS)); + if(pui8RawState) + { + *pui8RawState = (uint8_t)~ui32Data; + } + + // + // Determine the switches that are at a different state than the debounced + // state. + // + ui32Delta = ui32Data ^ g_ui8ButtonStates; + + // + // Increment the clocks by one. + // + ui8SwitchClockA ^= ui8SwitchClockB; + ui8SwitchClockB = ~ui8SwitchClockB; + + // + // Reset the clocks corresponding to switches that have not changed state. + // + ui8SwitchClockA &= ui32Delta; + ui8SwitchClockB &= ui32Delta; + + // + // Get the new debounced switch state. + // + g_ui8ButtonStates &= ui8SwitchClockA | ui8SwitchClockB; + g_ui8ButtonStates |= (~(ui8SwitchClockA | ui8SwitchClockB)) & ui32Data; + + // + // Determine the switches that just changed debounced state. + // + ui32Delta ^= (ui8SwitchClockA | ui8SwitchClockB); + + // + // Store the bit mask for the buttons that have changed for return to + // caller. + // + if(pui8Delta) + { + *pui8Delta = (uint8_t)ui32Delta; + } + + // + // Return the debounced buttons states to the caller. Invert the bit + // sense so that a '1' indicates the button is pressed, which is a + // sensible way to interpret the return value. + // + return(~g_ui8ButtonStates); +} + +//***************************************************************************** +// +//! Initializes the GPIO pins used by the board pushbuttons. +//! +//! This function must be called during application initialization to +//! configure the GPIO pins to which the pushbuttons are attached. It enables +//! the port used by the buttons and configures each button GPIO as an input +//! with a weak pull-up. +//! +//! \return None. +// +//***************************************************************************** +void +ButtonsInit(void) +{ + // + // Enable the GPIO port to which the pushbuttons are connected. + // + MAP_SysCtlPeripheralEnable(BUTTONS_GPIO_PERIPH); + + // + // Set each of the button GPIO pins as an input with a pull-up. + // + MAP_GPIODirModeSet(BUTTONS_GPIO_BASE, ALL_BUTTONS, GPIO_DIR_MODE_IN); + MAP_GPIOPadConfigSet(BUTTONS_GPIO_BASE, ALL_BUTTONS, + GPIO_STRENGTH_2MA, GPIO_PIN_TYPE_STD_WPU); + + // + // Initialize the debounced button state with the current state read from + // the GPIO bank. + // + g_ui8ButtonStates = MAP_GPIOPinRead(BUTTONS_GPIO_BASE, ALL_BUTTONS); +} + +//***************************************************************************** +// +// Close the Doxygen group. +//! @} +// +//***************************************************************************** -- cgit v1.3.1