Adam Kucybala
mbed library sources
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mbed-src
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mbed official
Revision 112:a7168c414ef2, committed 2014-03-07
- Comitter:
- mbed_official
- Date:
- Fri Mar 07 16:00:07 2014 +0000
- Parent:
- 111:ae4891ca7084
- Child:
- 113:65a335a675de
- Commit message:
- Synchronized with git revision 50b949b631f36d800e0008780cf33062071b4fa3
Full URL: https://github.com/mbedmicro/mbed/commit/50b949b631f36d800e0008780cf33062071b4fa3/
Protection against concurrent access to USBHost
Changed in this revision
--- a/targets/hal/TARGET_NXP/TARGET_LPC15XX/device.h Thu Mar 06 10:00:06 2014 +0000 +++ b/targets/hal/TARGET_NXP/TARGET_LPC15XX/device.h Fri Mar 07 16:00:07 2014 +0000 @@ -40,7 +40,7 @@ #define DEVICE_ETHERNET 0 -#define DEVICE_PWMOUT 0 +#define DEVICE_PWMOUT 1 #define DEVICE_SEMIHOST 0 #define DEVICE_LOCALFILESYSTEM 0
--- a/targets/hal/TARGET_NXP/TARGET_LPC15XX/objects.h Thu Mar 06 10:00:06 2014 +0000
+++ b/targets/hal/TARGET_NXP/TARGET_LPC15XX/objects.h Fri Mar 07 16:00:07 2014 +0000
@@ -29,6 +29,11 @@
uint32_t ch;
};
+struct pwmout_s {
+ LPC_SCT0_Type* pwm;
+ uint32_t pwm_ch;
+};
+
struct serial_s {
LPC_USART0_Type *uart;
unsigned char index;
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/targets/hal/TARGET_NXP/TARGET_LPC15XX/pwmout_api.c Fri Mar 07 16:00:07 2014 +0000
@@ -0,0 +1,169 @@
+/* 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 "pwmout_api.h"
+#include "cmsis.h"
+#include "pinmap.h"
+#include "error.h"
+
+static LPC_SCT0_Type *SCTs[4] = {
+ (LPC_SCT0_Type*)LPC_SCT0,
+ (LPC_SCT0_Type*)LPC_SCT1,
+ (LPC_SCT0_Type*)LPC_SCT2,
+ (LPC_SCT0_Type*)LPC_SCT3,
+};
+
+// bit flags for used SCTs
+static unsigned char sct_used = 0;
+static int get_available_sct(void) {
+ int i;
+ // start from 1, since 0 is used by ticker at the moment
+ for (i=1; i<4; i++) {
+ if ((sct_used & (1 << i)) == 0)
+ return i;
+ }
+ return -1;
+}
+
+void pwmout_init(pwmout_t* obj, PinName pin) {
+ if (pin == (uint32_t)NC)
+ error("PwmOut pin mapping failed");
+
+ int sct_n = get_available_sct();
+ if (sct_n == -1) {
+ error("No available SCT");
+ }
+
+ sct_used |= (1 << sct_n);
+ obj->pwm = SCTs[sct_n];
+ obj->pwm_ch = sct_n;
+
+ LPC_SCT0_Type* pwm = obj->pwm;
+
+ // Enable the SCT clock
+ LPC_SYSCON->SYSAHBCLKCTRL1 |= (1 << (obj->pwm_ch + 2));
+
+ // Clear peripheral reset the SCT:
+ LPC_SYSCON->PRESETCTRL1 |= (1 << (obj->pwm_ch + 2));
+ LPC_SYSCON->PRESETCTRL1 &= ~(1 << (obj->pwm_ch + 2));
+
+ switch(obj->pwm_ch) {
+ case 1:
+ // SCT1_OUT0
+ LPC_SWM->PINASSIGN[8] &= ~0x000000FF;
+ LPC_SWM->PINASSIGN[8] |= (pin);
+ break;
+ case 2:
+ // SCT2_OUT0
+ LPC_SWM->PINASSIGN[8] &= ~0xFF000000;
+ LPC_SWM->PINASSIGN[8] |= (pin << 24);
+ break;
+ case 3:
+ // SCT3_OUT0
+ LPC_SWM->PINASSIGN[9] &= ~0x00FF0000;
+ LPC_SWM->PINASSIGN[9] |= (pin << 16);
+ break;
+ default:
+ break;
+ }
+
+ // Two 16-bit counters, autolimit
+ pwm->CONFIG &= ~(0x1);
+ pwm->CONFIG |= (1 << 17);
+
+ // halt and clear the counter
+ pwm->CTRL |= (1 << 2) | (1 << 3);
+
+ // System Clock -> us_ticker (1)MHz
+ pwm->CTRL &= ~(0x7F << 5);
+ pwm->CTRL |= (((SystemCoreClock/1000000 - 1) & 0x7F) << 5);
+
+ // Match reload register
+ pwm->MATCHREL0 = 20000; // 20ms
+ pwm->MATCHREL1 = (pwm->MATCHREL0 / 4); // 50% duty
+
+ pwm->OUT0_SET = (1 << 0); // event 0
+ pwm->OUT0_CLR = (1 << 1); // event 1
+
+ pwm->EV0_CTRL = (1 << 12);
+ pwm->EV0_STATE = 0xFFFFFFFF;
+ pwm->EV1_CTRL = (1 << 12) | (1 << 0);
+ pwm->EV1_STATE = 0xFFFFFFFF;
+
+ // unhalt the counter:
+ // - clearing bit 2 of the CTRL register
+ pwm->CTRL &= ~(1 << 2);
+
+ // default to 20ms: standard for servos, and fine for e.g. brightness control
+ pwmout_period_ms(obj, 20);
+ pwmout_write (obj, 0);
+}
+
+void pwmout_free(pwmout_t* obj) {
+ // Disable the SCT clock
+ LPC_SYSCON->SYSAHBCLKCTRL1 &= ~(1 << (obj->pwm_ch + 2));
+ sct_used &= ~(1 << obj->pwm_ch);
+}
+
+void pwmout_write(pwmout_t* obj, float value) {
+ LPC_SCT0_Type* pwm = obj->pwm;
+ if (value < 0.0f) {
+ value = 0.0;
+ } else if (value > 1.0f) {
+ value = 1.0;
+ }
+ uint32_t t_off = pwm->MATCHREL0 - (uint32_t)((float)(pwm->MATCHREL0) * value);
+ uint32_t t_on = (uint32_t)((float)(pwm->MATCHREL0) * value);
+ pwm->MATCHREL1 = t_on;
+}
+
+float pwmout_read(pwmout_t* obj) {
+ uint32_t t_off = obj->pwm->MATCHREL0;
+ uint32_t t_on = obj->pwm->MATCHREL1;
+ float v = (float)t_on/(float)t_off;
+ return (v > 1.0f) ? (1.0f) : (v);
+}
+
+void pwmout_period(pwmout_t* obj, float seconds) {
+ pwmout_period_us(obj, seconds * 1000000.0f);
+}
+
+void pwmout_period_ms(pwmout_t* obj, int ms) {
+ pwmout_period_us(obj, ms * 1000);
+}
+
+// Set the PWM period, keeping the duty cycle the same.
+void pwmout_period_us(pwmout_t* obj, int us) {
+ LPC_SCT0_Type* pwm = obj->pwm;
+ uint32_t t_off = pwm->MATCHREL0;
+ uint32_t t_on = pwm->MATCHREL1;
+ float v = (float)t_on/(float)t_off;
+ pwm->MATCHREL0 = (uint64_t)us;
+ pwm->MATCHREL1 = (uint64_t)((float)us * (float)v);
+}
+
+void pwmout_pulsewidth(pwmout_t* obj, float seconds) {
+ pwmout_pulsewidth_us(obj, seconds * 1000000.0f);
+}
+
+void pwmout_pulsewidth_ms(pwmout_t* obj, int ms) {
+ pwmout_pulsewidth_us(obj, ms * 1000);
+}
+
+void pwmout_pulsewidth_us(pwmout_t* obj, int us) {
+ obj->pwm->MATCHREL1 = (uint64_t)us;
+}
+