tool/mbed/mbed-sdk/libraries/mbed/targets/hal/TARGET_NXP/TARGET_LPC11UXX/sleep.c

   1 /* mbed Microcontroller Library
   2  * Copyright (c) 2006-2013 ARM Limited
   3  *
   4  * Licensed under the Apache License, Version 2.0 (the "License");
   5  * you may not use this file except in compliance with the License.
   6  * You may obtain a copy of the License at
   7  *
   8  *     http://www.apache.org/licenses/LICENSE-2.0
   9  *
  10  * Unless required by applicable law or agreed to in writing, software
  11  * distributed under the License is distributed on an "AS IS" BASIS,
  12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  13  * See the License for the specific language governing permissions and
  14  * limitations under the License.
  15  */
  16 #include "sleep_api.h"
  17 #include "cmsis.h"
  18 #include "mbed_interface.h"
  19
  20 void sleep(void) {
  21     // ensure debug is disconnected
  22     #if DEVICE_SEMIHOST
  23     mbed_interface_disconnect();
  24     #endif
  25
  26     // PCON[PD] set to sleep
  27     LPC_PMU->PCON = 0x0;
  28
  29     // SRC[SLEEPDEEP] set to 0 = sleep
  30     SCB->SCR &= ~SCB_SCR_SLEEPDEEP_Msk;
  31
  32     // wait for interrupt
  33     __WFI();
  34 }
  35
  36 /*
  37 * The mbed lpc1768 does not support the deepsleep mode
  38 * as a debugger is connected to it (the mbed interface).
  39 *
  40 * As mentionned in an application note from NXP:
  41 *
  42 *       http://www.po-star.com/public/uploads/20120319123122_141.pdf
  43 *
  44 *       {{{
  45 *       The user should be aware of certain limitations during debugging.
  46 *       The most important is that, due to limitations of the Cortex-M3
  47 *       integration, the LPC17xx cannot wake up in the usual manner from
  48 *       Deep Sleep and Power-down modes. It is recommended not to use these
  49 *       modes during debug. Once an application is downloaded via JTAG/SWD
  50 *       interface, the USB to SWD/JTAG debug adapter (Keil ULINK2 for example)
  51 *       should be removed from the target board, and thereafter, power cycle
  52 *       the LPC17xx to allow wake-up from deep sleep and power-down modes
  53 *       }}}
  54 *
  55 *       As the interface firmware does not reset the target when a
  56 *       mbed_interface_disconnect() semihosting call is made, the
  57 *       core cannot wake-up from deepsleep.
  58 *
  59 *       We treat a deepsleep() as a normal sleep().
  60 */
  61
  62 void deepsleep(void) {
  63     // ensure debug is disconnected
  64     #if DEVICE_SEMIHOST
  65     mbed_interface_disconnect();
  66     #endif
  67
  68     // PCON[PD] set to deepsleep
  69     LPC_PMU->PCON = 0x1;
  70
  71     // SRC[SLEEPDEEP] set to 1 = deep sleep
  72     SCB->SCR |= SCB_SCR_SLEEPDEEP_Msk;
  73
  74     // Power up everything after powerdown
  75     LPC_SYSCON->PDAWAKECFG &= 0xFFFFF800;
  76
  77     // wait for interrupt
  78     __WFI();
  79 }