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tinyUSB/demos/bsp/lpc43xx/CMSIS_LPC43xx_DriverLib/src/lpc43xx_scu.c
2013-09-12 14:27:22 +07:00

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/**********************************************************************
* $Id$ lpc43xx_scu.c 2011-06-02
*//**
* @file lpc43xx_scu.c
* @brief Contains all functions support for SCU firmware library on lpc43xx
* @version 1.0
* @date 02. June. 2011
* @author NXP MCU SW Application Team
*
* Copyright(C) 2011, NXP Semiconductor
* All rights reserved.
*
***********************************************************************
* Software that is described herein is for illustrative purposes only
* which provides customers with programming information regarding the
* products. This software is supplied "AS IS" without any warranties.
* NXP Semiconductors assumes no responsibility or liability for the
* use of the software, conveys no license or title under any patent,
* copyright, or mask work right to the product. NXP Semiconductors
* reserves the right to make changes in the software without
* notification. NXP Semiconductors also make no representation or
* warranty that such application will be suitable for the specified
* use without further testing or modification.
* Permission to use, copy, modify, and distribute this software and its
* documentation is hereby granted, under NXP Semiconductors<72>
* relevant copyright in the software, without fee, provided that it
* is used in conjunction with NXP Semiconductors microcontrollers. This
* copyright, permission, and disclaimer notice must appear in all copies of
* this code.
**********************************************************************/
/* Peripheral group ----------------------------------------------------------- */
/** @addtogroup SCU
* @{
*/
/* Includes ------------------------------------------------------------------- */
#include "LPC43xx.h" /* lpc43xx definitions */
#include "lpc_types.h"
#include "lpc43xx_scu.h"
/* Pin modes
* =========
* The EPUN and EPD bits in the SFS registers allow the selection of weak on-chip
* pull-up or pull-down resistors with a typical value of 50 kOhm for each pin or the
* selection of the repeater mode.
* The possible on-chip resistor configurations are pull-up enabled, pull-down enabled, or no
* pull-up/pull-down. The default value is pull-up enabled.
*
* The repeater mode enables the pull-up resistor if the pin is at a logic HIGH and enables
* the pull-down resistor if the pin is at a logic LOW. This causes the pin to retain its last
* known state if it is configured as an input and is not driven externally. Repeater mode may
* typically be used to prevent a pin from floating (and potentially using significant power if it
* floats to an indeterminate state) if it is temporarily not driven.
* Repeater mode is enabled when both pull-up and pull-down are enabled.
*
* To be able to receive a digital signal, the input buffer must be enabled through bit EZI in
* the pin configuration registers. By default, the input buffer is disabled.
* For pads that support both a digital and an analog function, the input buffer must be
* disabled before enabling the analog function.
*
* All digital pins support a programmable glitch filter (bit ZIF), which can be switched on or
* off. By default, the glitch filter is on. The glitch filter should be disabled for
* clocking signals with frequencies higher than 30 MHz.
*
* Normal-drive and high-speed pins support a programmable slew rate (bit EHS) to select
* between lower noise and low speed or higher noise and high speed . The typical
* frequencies supported are 50 MHz/80 MHz for normal-drive pins and 75 MHz/180 MHz for
* high-speed pins.
*/
/*********************************************************************//**
* @brief Configure pin function
* @param[in] port Port number, should be: 0..15
* @param[in] pin Pin number, should be: 0..31
* @param[in] mode Pin mode, should be:
* - MD_PUP :Pull-up enabled
* - MD_BUK :Plain input
* - MD_PLN :Repeater mode
* - MD_PDN :Pull-down enabled
* - MD_EHS :Slew rate
* - MD_EZI :Input buffer enable
* - MD_ZI :Glitch filter enabled
* - MD_EHD0 :High drive 8 mA
* - MD_EHD1 :High drive 14 mA
* - MD_EHD2 :High drive 20 mA
* @param[in] func Function mode, should be:
* - FUNC0 :Function 0
* - FUNC1 :Function 1
* - FUNC2 :Function 2
* - FUNC3 :Function 3
* - FUNC4 :Function 4
* - FUNC5 :Function 5
* - FUNC6 :Function 6
* - FUNC7 :Function 7
* @return None
**********************************************************************/
void scu_pinmux(uint8_t port, uint8_t pin, uint8_t mode, uint8_t func)
{
uint32_t * scu_base=(uint32_t*)(LPC_SCU_BASE);
scu_base[(PORT_OFFSET*port+PIN_OFFSET*pin)/4]=mode+func;
} /* scu_pinmux */
/**
* @}
*/