/* ---------------------------------------------------------------------------- | |
* SAM Software Package License | |
* ---------------------------------------------------------------------------- | |
* Copyright (c) 2012, Atmel Corporation | |
* | |
* All rights reserved. | |
* | |
* Redistribution and use in source and binary forms, with or without | |
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* - Redistributions of source code must retain the above copyright notice, | |
* this list of conditions and the disclaimer below. | |
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* Atmel's name may not be used to endorse or promote products derived from | |
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* DISCLAIMER: THIS SOFTWARE IS PROVIDED BY ATMEL "AS IS" AND ANY EXPRESS OR | |
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*/ | |
/** \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() | |
* -# Receive data from the receiver using SSC_Read() | |
* -# Disable the transmitter and/or the receiver using SSC_DisableTransmitter() | |
* and SSC_DisableReceiver() | |
* | |
* For more accurate information, please look at the SSC 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 ssc Pointer to an SSC instance. | |
* \param bitRate bit rate. | |
* \param masterClock master clock. | |
*/ | |
void SSC_Configure(Ssc *ssc, uint32_t bitRate, uint32_t masterClock) | |
{ | |
uint32_t id; | |
// uint32_t maxClock; | |
id = ID_SSC ; | |
// maxClock = PMC_SetPeriMaxClock(id, masterClock); | |
/* Reset, disable receiver & transmitter */ | |
ssc->SSC_CR = SSC_CR_RXDIS | SSC_CR_TXDIS | SSC_CR_SWRST; | |
/* Configure clock frequency */ | |
if (bitRate != 0) { | |
ssc->SSC_CMR = masterClock / (2 * bitRate); | |
} | |
else { | |
ssc->SSC_CMR = 0; | |
} | |
/* Enable SSC peripheral clock */ | |
PMC_EnablePeripheral(id); | |
} | |
/** | |
* \brief Configures the transmitter of a SSC peripheral. | |
* \param ssc Pointer to an SSC instance. | |
* \param tcmr Transmit Clock Mode Register value. | |
* \param tfmr Transmit Frame Mode Register value. | |
*/ | |
void SSC_ConfigureTransmitter(Ssc *ssc,uint32_t tcmr, uint32_t tfmr) | |
{ | |
ssc->SSC_TCMR = tcmr; | |
ssc->SSC_TFMR = tfmr; | |
} | |
/** | |
* \brief Configures the receiver of a SSC peripheral. | |
* \param ssc Pointer to an SSC instance. | |
* \param rcmr Receive Clock Mode Register value. | |
* \param rfmr Receive Frame Mode Register value. | |
*/ | |
void SSC_ConfigureReceiver(Ssc *ssc, uint32_t rcmr, uint32_t rfmr) | |
{ | |
ssc->SSC_RCMR = rcmr; | |
ssc->SSC_RFMR = rfmr; | |
} | |
/** | |
* \brief Enables the transmitter of a SSC peripheral. | |
* \param ssc Pointer to an SSC instance. | |
*/ | |
void SSC_EnableTransmitter(Ssc *ssc) | |
{ | |
ssc->SSC_CR = SSC_CR_TXEN; | |
} | |
/** | |
* \brief Disables the transmitter of a SSC peripheral. | |
* \param ssc Pointer to an SSC instance. | |
*/ | |
void SSC_DisableTransmitter(Ssc *ssc) | |
{ | |
ssc->SSC_CR = SSC_CR_TXDIS; | |
} | |
/** | |
* \brief Enables the receiver of a SSC peripheral. | |
* \param ssc Pointer to an SSC instance. | |
*/ | |
void SSC_EnableReceiver(Ssc *ssc) | |
{ | |
ssc->SSC_CR = SSC_CR_RXEN; | |
} | |
/** | |
* \brief Disables the receiver of a SSC peripheral. | |
* \param ssc Pointer to an SSC instance. | |
*/ | |
void SSC_DisableReceiver(Ssc *ssc) | |
{ | |
ssc->SSC_CR = SSC_CR_RXDIS; | |
} | |
/** | |
* \brief Enables one or more interrupt sources of a SSC peripheral. | |
* \param ssc Pointer to an SSC instance. | |
* \param sources Bitwise OR of selected interrupt sources. | |
*/ | |
void SSC_EnableInterrupts(Ssc *ssc, uint32_t sources) | |
{ | |
ssc->SSC_IER = sources; | |
} | |
/** | |
* \brief Disables one or more interrupt sources of a SSC peripheral. | |
* \param ssc Pointer to an SSC instance. | |
* \param sources Bitwise OR of selected interrupt sources. | |
*/ | |
void SSC_DisableInterrupts(Ssc *ssc, 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 ssc Pointer to an SSC instance. | |
* \param frame Data frame to send. | |
*/ | |
void SSC_Write(Ssc *ssc, 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. | |
* \param ssc Pointer to an SSC instance. | |
*/ | |
uint32_t SSC_Read(Ssc *ssc) | |
{ | |
while ((ssc->SSC_SR & SSC_SR_RXRDY) == 0); | |
return ssc->SSC_RHR; | |
} | |
/** | |
* \brief Return 1 if one frame is received, 0 otherwise. | |
* \param ssc Pointer to an SSC instance. | |
*/ | |
uint8_t SSC_IsRxReady(Ssc *ssc) | |
{ | |
return ((ssc->SSC_SR & SSC_SR_RXRDY) > 0); | |
} | |