From 98f9d442b44dbe2e3e4b3c8296be7e78d5d05450 Mon Sep 17 00:00:00 2001 From: Harald Welte Date: Sun, 24 Jul 2011 09:39:28 +0200 Subject: initial import of the usb ccid example for the sam7s --- at91lib/peripherals/pit/pit.c | 122 ++++++++++++++++++++++++++++++++++++++++++ at91lib/peripherals/pit/pit.h | 77 ++++++++++++++++++++++++++ 2 files changed, 199 insertions(+) create mode 100644 at91lib/peripherals/pit/pit.c create mode 100644 at91lib/peripherals/pit/pit.h (limited to 'at91lib/peripherals/pit') diff --git a/at91lib/peripherals/pit/pit.c b/at91lib/peripherals/pit/pit.c new file mode 100644 index 0000000..f15610c --- /dev/null +++ b/at91lib/peripherals/pit/pit.c @@ -0,0 +1,122 @@ +/* ---------------------------------------------------------------------------- + * ATMEL Microcontroller Software Support + * ---------------------------------------------------------------------------- + * Copyright (c) 2008, 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. + * ---------------------------------------------------------------------------- + */ + +//------------------------------------------------------------------------------ +// Headers +//------------------------------------------------------------------------------ + +#include "pit.h" +#include + +//------------------------------------------------------------------------------ +// Global functions +//------------------------------------------------------------------------------ + +//------------------------------------------------------------------------------ +/// Initialize the Periodic Interval Timer to generate a tick at the specified +/// period, given the current master clock frequency. +/// \param period Period in µsecond. +/// \param pit_frequency Master clock frequency in MHz. +//------------------------------------------------------------------------------ +void PIT_Init(unsigned int period, unsigned int pit_frequency) +{ + AT91C_BASE_PITC->PITC_PIMR = period? (period * pit_frequency + 8) >> 4 : 0; + AT91C_BASE_PITC->PITC_PIMR |= AT91C_PITC_PITEN; +} + +//------------------------------------------------------------------------------ +/// Set the Periodic Interval Value of the PIT. +/// \param piv PIV value to set. +//------------------------------------------------------------------------------ +void PIT_SetPIV(unsigned int piv) +{ + AT91C_BASE_PITC->PITC_PIMR = (AT91C_BASE_PITC->PITC_PIMR & AT91C_PITC_PIV) + | piv; +} + +//------------------------------------------------------------------------------ +/// Enables the PIT if this is not already the case. +//------------------------------------------------------------------------------ +void PIT_Enable(void) +{ + AT91C_BASE_PITC->PITC_PIMR |= AT91C_PITC_PITEN; +} + +//---------------------------------------------------------------------------- +/// Enable the PIT periodic interrupt. +//---------------------------------------------------------------------------- +void PIT_EnableIT(void) +{ + AT91C_BASE_PITC->PITC_PIMR |= AT91C_PITC_PITIEN; +} + +//------------------------------------------------------------------------------ +/// Disables the PIT periodic interrupt. +//------------------------------------------------------------------------------ +void PIT_DisableIT(void) +{ + AT91C_BASE_PITC->PITC_PIMR &= ~AT91C_PITC_PITIEN; +} + +//------------------------------------------------------------------------------ +/// Returns the value of the PIT mode register. +/// \return PIT_MR value. +//------------------------------------------------------------------------------ +unsigned int PIT_GetMode(void) +{ + return AT91C_BASE_PITC->PITC_PIMR; +} + +//------------------------------------------------------------------------------ +/// Returns the value of the PIT status register, clearing it as a side effect. +/// \return PIT_SR value. +//------------------------------------------------------------------------------ +unsigned int PIT_GetStatus(void) +{ + return AT91C_BASE_PITC->PITC_PISR; +} + +//------------------------------------------------------------------------------ +/// Returns the value of the PIT Image Register, to read PICNT and CPIV without +/// clearing the current values. +/// \return PIT_PIIR value. +//------------------------------------------------------------------------------ +unsigned int PIT_GetPIIR(void) +{ + return AT91C_BASE_PITC->PITC_PIIR; +} + +//------------------------------------------------------------------------------ +/// Returns the value of the PIT Value Register, clearing it as a side effect. +/// \return PIT_PIVR value. +//------------------------------------------------------------------------------ +unsigned int PIT_GetPIVR(void) +{ + return AT91C_BASE_PITC->PITC_PIVR; +} diff --git a/at91lib/peripherals/pit/pit.h b/at91lib/peripherals/pit/pit.h new file mode 100644 index 0000000..12aad31 --- /dev/null +++ b/at91lib/peripherals/pit/pit.h @@ -0,0 +1,77 @@ +/* ---------------------------------------------------------------------------- + * ATMEL Microcontroller Software Support + * ---------------------------------------------------------------------------- + * Copyright (c) 2008, 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. + * ---------------------------------------------------------------------------- + */ + +//------------------------------------------------------------------------------ +/// \unit +/// +/// !Purpose +/// +/// Interface for configuration the Periodic Interval Timer (PIT) peripheral. +/// +/// !Usage +/// +/// -# Initialize the PIT with the desired period using PIT_Init(). +/// Alternatively, the Periodic Interval Value (PIV) can be configured +/// manually using PIT_SetPIV(). +/// -# Start the PIT counting using PIT_Enable(). +/// -# Enable & disable the PIT interrupt using PIT_EnableIT() and +/// PIT_DisableIT(). +/// -# Retrieve the current status of the PIT using PIT_GetStatus(). +/// -# To get the current value of the internal counter and the number of ticks +/// that have occurred, use either PIT_GetPIVR() or PIT_GetPIIR() depending +/// on whether you want the values to be cleared or not. +//------------------------------------------------------------------------------ + +#ifndef PIT_H +#define PIT_H + +//------------------------------------------------------------------------------ +// Global Functions +//------------------------------------------------------------------------------ + +extern void PIT_Init(unsigned int period, unsigned int pit_frequency); + +extern void PIT_SetPIV(unsigned int piv); + +extern void PIT_Enable(void); + +extern void PIT_EnableIT(void); + +extern void PIT_DisableIT(void); + +extern unsigned int PIT_GetMode(void); + +extern unsigned int PIT_GetStatus(void); + +extern unsigned int PIT_GetPIIR(void); + +extern unsigned int PIT_GetPIVR(void); + +#endif //#ifndef PIT_H + -- cgit v1.2.3