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//-----------------------------------------------------------------------------
// ATMEL Microcontroller Software Support - ROUSSET -
//-----------------------------------------------------------------------------
// 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.
//-----------------------------------------------------------------------------
// File Name : Cstartup_SAM7.c
// Object : Low level initialisations written in C for Tools
// For AT91SAM7X256 with 2 flash plane
// Creation : JPP 14-Sep-2006
//-----------------------------------------------------------------------------
#include "project.h"
// The following functions must be write in ARM mode this function called
// directly by exception vector
extern void AT91F_Spurious_handler(void);
extern void AT91F_Default_IRQ_handler(void);
extern void AT91F_Default_FIQ_handler(void);
//*----------------------------------------------------------------------------
//* \fn AT91F_LowLevelInit
//* \brief This function performs very low level HW initialization
//* this function can use a Stack, depending the compilation
//* optimization mode
//*----------------------------------------------------------------------------
void AT91F_LowLevelInit(void) @ "ICODE"
{
unsigned char i;
///////////////////////////////////////////////////////////////////////////
// EFC Init
///////////////////////////////////////////////////////////////////////////
AT91C_BASE_MC->MC_FMR = AT91C_MC_FWS_1FWS ;
///////////////////////////////////////////////////////////////////////////
// Init PMC Step 1. Enable Main Oscillator
// Main Oscillator startup time is board specific:
// Main Oscillator Startup Time worst case (3MHz) corresponds to 15ms
// (0x40 for AT91C_CKGR_OSCOUNT field)
///////////////////////////////////////////////////////////////////////////
AT91C_BASE_PMC->PMC_MOR = (( AT91C_CKGR_OSCOUNT & (0x40 <<8) | AT91C_CKGR_MOSCEN ));
// Wait Main Oscillator stabilization
while(!(AT91C_BASE_PMC->PMC_SR & AT91C_PMC_MOSCS));
///////////////////////////////////////////////////////////////////////////
// Init PMC Step 2.
// Set PLL to 96MHz (96,109MHz) and UDP Clock to 48MHz
// PLL Startup time depends on PLL RC filter: worst case is choosen
// UDP Clock (48,058MHz) is compliant with the Universal Serial Bus
// Specification (+/- 0.25% for full speed)
///////////////////////////////////////////////////////////////////////////
AT91C_BASE_PMC->PMC_PLLR = AT91C_CKGR_USBDIV_1 |
(16 << 8) |
(AT91C_CKGR_MUL & (72 << 16)) |
(AT91C_CKGR_DIV & 14);
// Wait for PLL stabilization
while( !(AT91C_BASE_PMC->PMC_SR & AT91C_PMC_LOCK) );
// Wait until the master clock is established for the case we already
// turn on the PLL
while( !(AT91C_BASE_PMC->PMC_SR & AT91C_PMC_MCKRDY) );
///////////////////////////////////////////////////////////////////////////
// Init PMC Step 3.
// Selection of Master Clock MCK equal to (Processor Clock PCK) PLL/2=48MHz
// The PMC_MCKR register must not be programmed in a single write operation
// (see. Product Errata Sheet)
///////////////////////////////////////////////////////////////////////////
AT91C_BASE_PMC->PMC_MCKR = AT91C_PMC_PRES_CLK_2;
// Wait until the master clock is established
while( !(AT91C_BASE_PMC->PMC_SR & AT91C_PMC_MCKRDY) );
AT91C_BASE_PMC->PMC_MCKR |= AT91C_PMC_CSS_PLL_CLK;
// Wait until the master clock is established
while( !(AT91C_BASE_PMC->PMC_SR & AT91C_PMC_MCKRDY) );
///////////////////////////////////////////////////////////////////////////
// Disable Watchdog (write once register)
///////////////////////////////////////////////////////////////////////////
AT91C_BASE_WDTC->WDTC_WDMR = AT91C_WDTC_WDDIS;
///////////////////////////////////////////////////////////////////////////
// Init AIC: assign corresponding handler for each interrupt source
///////////////////////////////////////////////////////////////////////////
AT91C_BASE_AIC->AIC_SVR[0] = (int) AT91F_Default_FIQ_handler ;
for (i = 1; i < 31; i++) {
AT91C_BASE_AIC->AIC_SVR[i] = (int) AT91F_Default_IRQ_handler ;
}
AT91C_BASE_AIC->AIC_SPU = (unsigned int) AT91F_Spurious_handler;
}
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