Diff: targets/hal/TARGET_NXP/TARGET_LPC15XX/us_ticker.c

Revision:

0:9b334a45a8ff

Child:

144:ef7eb2e8f9f7

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/targets/hal/TARGET_NXP/TARGET_LPC15XX/us_ticker.c	Thu Oct 01 15:25:22 2015 +0300
@@ -0,0 +1,73 @@
+/* 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 <stddef.h>
+#include "us_ticker_api.h"
+#include "PeripheralNames.h"
+
+#define US_TICKER_TIMER_IRQn     RIT_IRQn
+
+int us_ticker_inited = 0;
+
+void us_ticker_init(void) {
+    if (us_ticker_inited) return;
+    us_ticker_inited = 1;
+    
+    // Enable the RIT clock
+    LPC_SYSCON->SYSAHBCLKCTRL1 |= (1 << 1);
+    
+    // Clear peripheral reset the RIT
+    LPC_SYSCON->PRESETCTRL1 |= (1 << 1);
+    LPC_SYSCON->PRESETCTRL1 &= ~(1 << 1);
+    
+    LPC_RIT->MASK = 0;
+    LPC_RIT->MASK_H = 0;
+    
+    LPC_RIT->COUNTER = 0;
+    LPC_RIT->COUNTER_H = 0;
+
+    LPC_RIT->COMPVAL = 0xffffffff;
+    LPC_RIT->COMPVAL_H = 0x0000ffff;
+
+    // Timer enable, enable for debug
+    LPC_RIT->CTRL = 0xC;
+    
+    NVIC_SetVector(US_TICKER_TIMER_IRQn, (uint32_t)us_ticker_irq_handler);
+    NVIC_EnableIRQ(US_TICKER_TIMER_IRQn);
+}
+
+uint32_t us_ticker_read() {
+    if (!us_ticker_inited)
+        us_ticker_init();
+    
+    uint64_t temp;
+    temp = LPC_RIT->COUNTER | ((uint64_t)LPC_RIT->COUNTER_H << 32);
+    temp /= (SystemCoreClock/1000000);
+    return (uint32_t)temp;
+}
+
+void us_ticker_set_interrupt(timestamp_t timestamp) {
+	uint64_t temp = ((uint64_t)timestamp * (SystemCoreClock/1000000));
+    LPC_RIT->COMPVAL = (temp & 0xFFFFFFFFL);
+    LPC_RIT->COMPVAL_H = ((temp >> 32)& 0x0000FFFFL);
+}
+
+void us_ticker_disable_interrupt(void) {
+    LPC_RIT->CTRL |= (1 << 3);
+}
+
+void us_ticker_clear_interrupt(void) {
+    LPC_RIT->CTRL |= (1 << 0);
+}