CC2650STK_fxns.c

/*
 * Copyright (c) 2018, Texas Instruments Incorporated
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * *  Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 *
 * *  Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * *  Neither the name of Texas Instruments Incorporated nor the names of
 *    its contributors may be used to endorse or promote products derived
 *    from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
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 * EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */
/*
 *  ====================== CC2650STK_fxns.c =========================================
 *  This file contains the board-specific initialization functions.
 */

#include <stdbool.h>
#include <stddef.h>
#include <stdint.h>

#include <ti/devices/DeviceFamily.h>
#include DeviceFamily_constructPath(driverlib/ioc.h)
#include DeviceFamily_constructPath(driverlib/cpu.h)

#include "Board.h"

/*
 *  ======== CC2650STK_sendExtFlashByte ========
 */
void CC2650STK_sendExtFlashByte(PIN_Handle pinHandle, uint8_t byte)
{
    uint8_t i;

    /* SPI Flash CS */
    PIN_setOutputValue(pinHandle, IOID_14, 0);

    for (i = 0; i < 8; i++) {
        PIN_setOutputValue(pinHandle, IOID_17, 0);  /* SPI Flash CLK */

        /* SPI Flash MOSI */
        PIN_setOutputValue(pinHandle, IOID_19, (byte >> (7 - i)) & 0x01);
        PIN_setOutputValue(pinHandle, IOID_17, 1);

        /*
         * Waste a few cycles to keep the CLK high for at
         * least 45% of the period.
         * 3 cycles per loop: 8 loops @ 48 Mhz = 0.5 us.
         */
        CPUdelay(8);
    }

    PIN_setOutputValue(pinHandle, IOID_17, 0);
    PIN_setOutputValue(pinHandle, IOID_14, 1);

    /*
     * Keep CS high at least 40 us
     * 3 cycles per loop: 700 loops @ 48 Mhz ~= 44 us
     */
    CPUdelay(700);
}

/*
 *  ======== CC2650STK_wakeUpExtFlash ========
 */
void CC2650STK_wakeUpExtFlash(void)
{
    PIN_Config extFlashPinTable[] = {
        IOID_14 | PIN_GPIO_OUTPUT_EN | PIN_GPIO_HIGH | PIN_PUSHPULL |
                PIN_INPUT_DIS | PIN_DRVSTR_MED,
        PIN_TERMINATE
    };
    PIN_State extFlashPinState;
    PIN_Handle extFlashPinHandle = PIN_open(&extFlashPinState, extFlashPinTable);

    /*
     *  To wake up we need to toggle the chip select at
     *  least 20 ns and ten wait at least 35 us.
     */

    /* Toggle chip select for ~20ns to wake ext. flash */
    PIN_setOutputValue(extFlashPinHandle, IOID_14, 0);
    /* 3 cycles per loop: 1 loop @ 48 Mhz ~= 62 ns */
    CPUdelay(1);
    PIN_setOutputValue(extFlashPinHandle, IOID_14, 1);
    /* 3 cycles per loop: 560 loops @ 48 Mhz ~= 35 us */
    CPUdelay(560);

    PIN_close(extFlashPinHandle);
}

/*
 *  ======== CC2650STK_shutDownExtFlash ========
 */
void CC2650STK_shutDownExtFlash(void)
{
    /*
     *  To be sure we are putting the flash into sleep and not waking it,
     *  we first have to make a wake up call
     */
    CC2650STK_wakeUpExtFlash();

    PIN_Config extFlashPinTable[] = {
        /* SPI Flash CS*/
        IOID_14 | PIN_GPIO_OUTPUT_EN | PIN_GPIO_HIGH | PIN_PUSHPULL |
                PIN_INPUT_DIS | PIN_DRVSTR_MED,
        /* SPI Flash CLK */
        IOID_17 | PIN_GPIO_OUTPUT_EN | PIN_GPIO_LOW | PIN_PUSHPULL |
                PIN_INPUT_DIS | PIN_DRVSTR_MED,
        /* SPI Flash MOSI */
        IOID_19 | PIN_GPIO_OUTPUT_EN | PIN_GPIO_LOW | PIN_PUSHPULL |
                PIN_INPUT_DIS | PIN_DRVSTR_MED,
        /* SPI Flash MISO */
        IOID_18 | PIN_INPUT_EN | PIN_PULLDOWN,
        PIN_TERMINATE
    };
    PIN_State extFlashPinState;
    PIN_Handle extFlashPinHandle = PIN_open(&extFlashPinState, extFlashPinTable);

    uint8_t extFlashShutdown = 0xB9;

    CC2650STK_sendExtFlashByte(extFlashPinHandle, extFlashShutdown);

    PIN_close(extFlashPinHandle);
}

/*
 *  ======== Board_initHook ========
 *  Called by Board_init() to perform board-specific initialization.
 */
void Board_initHook()
{
    CC2650STK_shutDownExtFlash();
}