Renamed main folder to firmware

firmware/atmel_softpack_libraries/libchip_sam3s/source/ssc.c

@@ -0,0 +1,247 @@
+/* ----------------------------------------------------------------------------
+ *         ATMEL Microcontroller Software Support
+ * ----------------------------------------------------------------------------
+ * Copyright (c) 2009, Atmel Corporation
+ *
+ * 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 disclaimer below.
+ *
+ * Atmel's name may not be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * DISCLAIMER: THIS SOFTWARE IS PROVIDED BY ATMEL "AS IS" AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT ARE
+ * DISCLAIMED. IN NO EVENT SHALL ATMEL 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; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
+ * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+ * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
+ * EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * ----------------------------------------------------------------------------
+ */
+
+/** \addtogroup ssc_module Working with SSC
+ * The SSC driver provides the interface to configure and use the SSC
+ * peripheral.
+ *
+ * !Usage
+ *
+ * -# Enable the SSC interface pins.
+ * -# Configure the SSC to operate at a specific frequency by calling
+ *    SSC_Configure(). This function enables the peripheral clock of the SSC,
+ *    but not its PIOs.
+ * -# Configure the transmitter and/or the receiver using the
+ *    SSC_ConfigureTransmitter() and SSC_ConfigureEmitter() functions.
+ * -# Enable the PIOs or the transmitter and/or the received.
+ * -# Enable the transmitter and/or the receiver using SSC_EnableTransmitter()
+ *    and SSC_EnableReceiver()
+ * -# Send data through the transmitter using SSC_Write() and SSC_WriteBuffer()
+ * -# Receive data from the receiver using SSC_Read() and SSC_ReadBuffer()
+ * -# Disable the transmitter and/or the receiver using SSC_DisableTransmitter()
+ *    and SSC_DisableReceiver()
+ *
+ * For more accurate information, please look at the RTC section of the
+ * Datasheet.
+ *
+ * Related files :\n
+ * \ref ssc.c\n
+ * \ref ssc.h.\n
+*/
+/*@{*/
+/*@}*/
+
+
+/**
+ * \file
+ *
+ * Implementation of Synchronous Serial (SSC) controller.
+ *
+ */
+
+/*----------------------------------------------------------------------------
+ *        Headers
+ *----------------------------------------------------------------------------*/
+
+#include "chip.h"
+
+/*----------------------------------------------------------------------------
+ *       Exported functions
+ *----------------------------------------------------------------------------*/
+
+/**
+ * \brief Configures a SSC peripheral.If the divided clock is not used, the master
+ * clock frequency can be set to 0.
+ * \note The emitter and transmitter are disabled by this function.
+ * \param bitRate  bit rate.
+ * \param masterClock  master clock.
+ */
+void SSC_Configure(uint32_t bitRate, uint32_t masterClock)
+{
+    /* Enable SSC peripheral clock */
+    PMC->PMC_PCER0 = 1 << ID_SSC;
+
+    /* Reset, disable receiver & transmitter */
+    SSC->SSC_CR = SSC_CR_RXDIS | SSC_CR_TXDIS | SSC_CR_SWRST;
+
+    SSC->SSC_PTCR = SSC_PTCR_RXTDIS | SSC_PTCR_TXTDIS;
+    /* Configure clock frequency */
+    if (bitRate != 0) {
+
+        SSC->SSC_CMR = masterClock / (2 * bitRate);
+    }
+    else {
+
+        SSC->SSC_CMR = 0;
+    }
+}
+
+/**
+ * \brief Configures the transmitter of a SSC peripheral.
+ * \param tcmr Transmit Clock Mode Register value.
+ * \param tfmr Transmit Frame Mode Register value.
+ */
+void SSC_ConfigureTransmitter(uint32_t tcmr, uint32_t tfmr)
+{
+    SSC->SSC_TCMR = tcmr;
+    SSC->SSC_TFMR = tfmr;
+}
+
+/**
+ * \brief Configures the receiver of a SSC peripheral.
+ * \param rcmr Receive Clock Mode Register value.
+ * \param rfmr Receive Frame Mode Register value.
+ */
+void SSC_ConfigureReceiver(uint32_t rcmr, uint32_t rfmr)
+{
+    SSC->SSC_RCMR = rcmr;
+    SSC->SSC_RFMR = rfmr;
+}
+
+/**
+ * \brief Enables the transmitter of a SSC peripheral.
+ */
+void SSC_EnableTransmitter(void)
+{
+    SSC->SSC_CR = SSC_CR_TXEN;
+}
+
+/**
+ * \brief Disables the transmitter of a SSC peripheral.
+ */
+void SSC_DisableTransmitter(void)
+{
+    SSC->SSC_CR = SSC_CR_TXDIS;
+}
+
+/**
+ * \brief Enables the receiver of a SSC peripheral.
+ */
+void SSC_EnableReceiver(void)
+{
+    SSC->SSC_CR = SSC_CR_RXEN;
+}
+
+/**
+ * \brief Disables the receiver of a SSC peripheral.
+ */
+void SSC_DisableReceiver(void)
+{
+    SSC->SSC_CR = SSC_CR_RXDIS;
+}
+
+/**
+ * \brief Enables one or more interrupt sources of a SSC peripheral.
+ * \param sources Bitwise OR of selected interrupt sources.
+ */
+void SSC_EnableInterrupts(uint32_t sources)
+{
+    SSC->SSC_IER = sources;
+}
+
+/**
+ * \brief Disables one or more interrupt sources of a SSC peripheral.
+ * \param sources Bitwise OR of selected interrupt sources.
+ */
+void SSC_DisableInterrupts(uint32_t sources)
+{
+    SSC->SSC_IDR = sources;
+}
+
+/**
+ * \brief Sends one data frame through a SSC peripheral. If another frame is currently
+ * being sent, this function waits for the previous transfer to complete.
+ * \param frame Data frame to send.
+ */
+void SSC_Write(uint32_t frame)
+{
+    while ((SSC->SSC_SR & SSC_SR_TXRDY) == 0);
+    SSC->SSC_THR = frame;
+}
+
+/**
+ * \brief Waits until one frame is received on a SSC peripheral, and returns it.
+ */
+uint32_t SSC_Read(void)
+{
+    while ((SSC->SSC_SR & SSC_SR_RXRDY) == 0);
+    return SSC->SSC_RHR;
+}
+
+/**
+ * \brief Sends the contents of a data buffer a SSC peripheral, using the PDC.
+ * \param buffer Data buffer to send.
+ * \param length Size of the data buffer.
+ * \return 1 if the buffer has been queued for transmission; otherwise returns 0.
+ */
+uint8_t SSC_WriteBuffer(void *buffer, uint32_t length)
+{
+    /* Check if first bank is free*/
+    if (SSC->SSC_TCR == 0) {
+
+        SSC->SSC_TPR = (uint32_t) buffer;
+        SSC->SSC_TCR = length;
+        SSC->SSC_PTCR = SSC_PTCR_TXTEN;
+        return 1;
+    }
+    /* Check if second bank is free*/
+    else if (SSC->SSC_TNCR == 0) {
+
+        SSC->SSC_TNPR = (uint32_t) buffer;
+        SSC->SSC_TNCR = length;
+        return 1;
+    }
+    return 0;
+}
+
+/**
+ * \brief Reads data coming from a SSC peripheral receiver and stores it into the
+ * giving buffer with PDC.
+ * \param buffer ata buffer used for reception.
+ * \param length Size of the data buffer.
+ * \return 1 if the buffer has been queued for reception; otherwise returns 0.
+ */
+uint8_t SSC_ReadBuffer(void *buffer, uint32_t length)
+{
+    /* Check if the first bank is free*/
+    if (SSC->SSC_RCR == 0) {
+
+        SSC->SSC_RPR = (uint32_t) buffer;
+        SSC->SSC_RCR = length;
+        SSC->SSC_PTCR = SSC_PTCR_RXTEN;
+        return 1;
+    }
+    /* Check if second bank is free*/
+    else if (SSC->SSC_RNCR == 0) {
+        SSC->SSC_RNPR = (uint32_t) buffer;
+        SSC->SSC_RNCR = length;
+        return 1;
+    }
+    return 0;
+}