pinmap.c

00001 /* mbed Microcontroller Library
00002  * Copyright (c) 2006-2013 ARM Limited
00003  *
00004  * Licensed under the Apache License, Version 2.0 (the "License");
00005  * you may not use this file except in compliance with the License.
00006  * You may obtain a copy of the License at
00007  *
00008  *     http://www.apache.org/licenses/LICENSE-2.0
00009  *
00010  * Unless required by applicable law or agreed to in writing, software
00011  * distributed under the License is distributed on an "AS IS" BASIS,
00012  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
00013  * See the License for the specific language governing permissions and
00014  * limitations under the License.
00015  */
00016 #include "pinmap.h"
00017 #include "error.h"
00018 
00019 #define LPC_IOCON0_BASE (LPC_IOCON_BASE)
00020 #define LPC_IOCON1_BASE (LPC_IOCON_BASE + 0x60)
00021 
00022 void pin_function(PinName pin, int function) {
00023     if (pin == (uint32_t)NC) return;
00024     
00025     uint32_t pin_number = (uint32_t)pin;
00026     
00027     __IO uint32_t *reg = (pin_number < 32) ?
00028             (__IO uint32_t*)(LPC_IOCON0_BASE + 4 * pin_number) :
00029             (__IO uint32_t*)(LPC_IOCON1_BASE + 4 * (pin_number - 32));
00030     
00031     // pin function bits: [2:0] -> 111 = (0x7)
00032     *reg = (*reg & ~0x7) | (function & 0x7);
00033 }
00034 
00035 void pin_mode(PinName pin, PinMode mode) {
00036     if (pin == (uint32_t)NC) { return; }
00037     
00038     uint32_t pin_number = (uint32_t)pin;
00039     uint32_t drain = ((uint32_t) mode & (uint32_t) OpenDrain) >> 2;
00040     
00041     __IO uint32_t *reg = (pin_number < 32) ?
00042             (__IO uint32_t*)(LPC_IOCON0_BASE + 4 * pin_number) :
00043             (__IO uint32_t*)(LPC_IOCON1_BASE + 4 * (pin_number - 32));
00044     uint32_t tmp = *reg;
00045     
00046     // pin mode bits: [4:3] -> 11000 = (0x3 << 3)
00047     tmp &= ~(0x3 << 3);
00048     tmp |= (mode & 0x3) << 3;
00049     
00050     // drain
00051     tmp &= ~(0x1 << 10);
00052     tmp |= drain << 10;
00053     
00054     *reg = tmp;
00055 }