Umar Naeem / mbed-dev

mbed library sources. Supersedes mbed-src.

Fork of mbed-dev by Umar Naeem

targets/hal/TARGET_NXP/TARGET_LPC176X/sleep.c@0:9b334a45a8ff, 2015-10-01 (annotated)

Committer:
bogdanm
Date:
Thu Oct 01 15:25:22 2015 +0300
Revision:
0:9b334a45a8ff
Child:
144:ef7eb2e8f9f7
Initial commit on mbed-dev



Replaces mbed-src (now inactive)

Who changed what in which revision?

UserRevisionLine numberNew contents of line
bogdanm 0:9b334a45a8ff 1 /* mbed Microcontroller Library
bogdanm 0:9b334a45a8ff 2 * Copyright (c) 2006-2013 ARM Limited
bogdanm 0:9b334a45a8ff 3 *
bogdanm 0:9b334a45a8ff 4 * Licensed under the Apache License, Version 2.0 (the "License");
bogdanm 0:9b334a45a8ff 5 * you may not use this file except in compliance with the License.
bogdanm 0:9b334a45a8ff 6 * You may obtain a copy of the License at
bogdanm 0:9b334a45a8ff 7 *
bogdanm 0:9b334a45a8ff 8 * http://www.apache.org/licenses/LICENSE-2.0
bogdanm 0:9b334a45a8ff 9 *
bogdanm 0:9b334a45a8ff 10 * Unless required by applicable law or agreed to in writing, software
bogdanm 0:9b334a45a8ff 11 * distributed under the License is distributed on an "AS IS" BASIS,
bogdanm 0:9b334a45a8ff 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
bogdanm 0:9b334a45a8ff 13 * See the License for the specific language governing permissions and
bogdanm 0:9b334a45a8ff 14 * limitations under the License.
bogdanm 0:9b334a45a8ff 15 */
bogdanm 0:9b334a45a8ff 16 #include "sleep_api.h"
bogdanm 0:9b334a45a8ff 17 #include "cmsis.h"
bogdanm 0:9b334a45a8ff 18 #include "mbed_interface.h"
bogdanm 0:9b334a45a8ff 19
bogdanm 0:9b334a45a8ff 20 void sleep(void) {
bogdanm 0:9b334a45a8ff 21
bogdanm 0:9b334a45a8ff 22 #if (DEVICE_SEMIHOST == 1)
bogdanm 0:9b334a45a8ff 23 // ensure debug is disconnected
bogdanm 0:9b334a45a8ff 24 mbed_interface_disconnect();
bogdanm 0:9b334a45a8ff 25 #endif
bogdanm 0:9b334a45a8ff 26
bogdanm 0:9b334a45a8ff 27 // PCON[PD] set to sleep
bogdanm 0:9b334a45a8ff 28 LPC_SC->PCON = 0x0;
bogdanm 0:9b334a45a8ff 29
bogdanm 0:9b334a45a8ff 30 // SRC[SLEEPDEEP] set to 0 = sleep
bogdanm 0:9b334a45a8ff 31 SCB->SCR &= ~SCB_SCR_SLEEPDEEP_Msk;
bogdanm 0:9b334a45a8ff 32
bogdanm 0:9b334a45a8ff 33 // wait for interrupt
bogdanm 0:9b334a45a8ff 34 __WFI();
bogdanm 0:9b334a45a8ff 35 }
bogdanm 0:9b334a45a8ff 36
bogdanm 0:9b334a45a8ff 37 /*
bogdanm 0:9b334a45a8ff 38 * The mbed lpc1768 does not support the deepsleep mode
bogdanm 0:9b334a45a8ff 39 * as a debugger is connected to it (the mbed interface).
bogdanm 0:9b334a45a8ff 40 *
bogdanm 0:9b334a45a8ff 41 * As mentionned in an application note from NXP:
bogdanm 0:9b334a45a8ff 42 *
bogdanm 0:9b334a45a8ff 43 * http://www.po-star.com/public/uploads/20120319123122_141.pdf
bogdanm 0:9b334a45a8ff 44 *
bogdanm 0:9b334a45a8ff 45 * {{{
bogdanm 0:9b334a45a8ff 46 * The user should be aware of certain limitations during debugging.
bogdanm 0:9b334a45a8ff 47 * The most important is that, due to limitations of the Cortex-M3
bogdanm 0:9b334a45a8ff 48 * integration, the LPC17xx cannot wake up in the usual manner from
bogdanm 0:9b334a45a8ff 49 * Deep Sleep and Power-down modes. It is recommended not to use these
bogdanm 0:9b334a45a8ff 50 * modes during debug. Once an application is downloaded via JTAG/SWD
bogdanm 0:9b334a45a8ff 51 * interface, the USB to SWD/JTAG debug adapter (Keil ULINK2 for example)
bogdanm 0:9b334a45a8ff 52 * should be removed from the target board, and thereafter, power cycle
bogdanm 0:9b334a45a8ff 53 * the LPC17xx to allow wake-up from deep sleep and power-down modes
bogdanm 0:9b334a45a8ff 54 * }}}
bogdanm 0:9b334a45a8ff 55 *
bogdanm 0:9b334a45a8ff 56 * As the interface firmware does not reset the target when a
bogdanm 0:9b334a45a8ff 57 * mbed_interface_disconnect() semihosting call is made, the
bogdanm 0:9b334a45a8ff 58 * core cannot wake-up from deepsleep.
bogdanm 0:9b334a45a8ff 59 *
bogdanm 0:9b334a45a8ff 60 * We treat a deepsleep() as a normal sleep().
bogdanm 0:9b334a45a8ff 61 */
bogdanm 0:9b334a45a8ff 62
bogdanm 0:9b334a45a8ff 63 void deepsleep(void) {
bogdanm 0:9b334a45a8ff 64
bogdanm 0:9b334a45a8ff 65 #if (DEVICE_SEMIHOST == 1)
bogdanm 0:9b334a45a8ff 66 // ensure debug is disconnected
bogdanm 0:9b334a45a8ff 67 mbed_interface_disconnect();
bogdanm 0:9b334a45a8ff 68 #endif
bogdanm 0:9b334a45a8ff 69
bogdanm 0:9b334a45a8ff 70 // PCON[PD] set to deepsleep
bogdanm 0:9b334a45a8ff 71 sleep();
bogdanm 0:9b334a45a8ff 72 }