Diff: targets/TARGET_NXP/TARGET_LPC176X/sleep.c

Revision:

0:f269e3021894

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/targets/TARGET_NXP/TARGET_LPC176X/sleep.c	Sun Oct 23 15:10:02 2016 +0000
@@ -0,0 +1,72 @@
+/* mbed Microcontroller Library
+ * Copyright (c) 2006-2013 ARM Limited
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+#include "sleep_api.h"
+#include "cmsis.h"
+#include "mbed_interface.h"
+
+void sleep(void) {
+
+#if (DEVICE_SEMIHOST == 1)
+    // ensure debug is disconnected
+    mbed_interface_disconnect();
+#endif
+
+    // PCON[PD] set to sleep
+    LPC_SC->PCON = 0x0;
+    
+    // SRC[SLEEPDEEP] set to 0 = sleep
+    SCB->SCR &= ~SCB_SCR_SLEEPDEEP_Msk;
+    
+    // wait for interrupt
+    __WFI();
+}
+
+/*
+* The mbed lpc1768 does not support the deepsleep mode
+* as a debugger is connected to it (the mbed interface).
+*
+* As mentionned in an application note from NXP:
+*
+*       http://www.po-star.com/public/uploads/20120319123122_141.pdf
+*
+*       {{{
+*       The user should be aware of certain limitations during debugging.
+*       The most important is that, due to limitations of the Cortex-M3
+*       integration, the LPC17xx cannot wake up in the usual manner from
+*       Deep Sleep and Power-down modes. It is recommended not to use these
+*       modes during debug. Once an application is downloaded via JTAG/SWD
+*       interface, the USB to SWD/JTAG debug adapter (Keil ULINK2 for example)
+*       should be removed from the target board, and thereafter, power cycle
+*       the LPC17xx to allow wake-up from deep sleep and power-down modes
+*       }}}
+*
+*       As the interface firmware does not reset the target when a
+*       mbed_interface_disconnect() semihosting call is made, the
+*       core cannot wake-up from deepsleep.
+*
+*       We treat a deepsleep() as a normal sleep().
+*/
+
+void deepsleep(void) {
+
+#if (DEVICE_SEMIHOST == 1)
+    // ensure debug is disconnected
+    mbed_interface_disconnect();
+#endif
+    
+    // PCON[PD] set to deepsleep
+    sleep();
+}