From ad009f46d58f4f555cd412aa2f2a267da01db4e0 Mon Sep 17 00:00:00 2001
From: gdisirio <gdisirio@35acf78f-673a-0410-8e92-d51de3d6d3f4>
Date: Tue, 5 Apr 2011 18:21:00 +0000
Subject: STM32 PWM driver optimization, changed the behavior of
 pwmChangePeriod().

git-svn-id: svn://svn.code.sf.net/p/chibios/svn/trunk@2869 35acf78f-673a-0410-8e92-d51de3d6d3f4
---
 testhal/STM32/PWM-ICU/main.c | 22 ++++++++++++++--------
 1 file changed, 14 insertions(+), 8 deletions(-)

(limited to 'testhal')

diff --git a/testhal/STM32/PWM-ICU/main.c b/testhal/STM32/PWM-ICU/main.c
index 3f7b6423e..1fd56c33a 100644
--- a/testhal/STM32/PWM-ICU/main.c
+++ b/testhal/STM32/PWM-ICU/main.c
@@ -89,7 +89,7 @@ int main(void) {
   palSetPad(IOPORT3, GPIOC_LED);
 
   /*
-   * Initializes the PWM driver 1.
+   * Initializes the PWM driver 1 and ICU driver 4.
    */
   pwmStart(&PWMD1, &pwmcfg);
   palSetPadMode(IOPORT1, 8, PAL_MODE_STM32_ALTERNATE_PUSHPULL);
@@ -98,26 +98,32 @@ int main(void) {
   chThdSleepMilliseconds(2000);
 
   /*
-   * Starts the channel 0 using 25% duty cycle.
+   * Starts the PWM channel 0 using 75% duty cycle.
    */
-  pwmEnableChannel(&PWMD1, 0, PWM_PERCENTAGE_TO_WIDTH(&PWMD1, 2500));
+  pwmEnableChannel(&PWMD1, 0, PWM_PERCENTAGE_TO_WIDTH(&PWMD1, 7500));
   chThdSleepMilliseconds(5000);
 
   /*
-   * Changes the channel 0 to 75% duty cycle.
+   * Changes the PWM channel 0 to 50% duty cycle.
    */
-  pwmEnableChannel(&PWMD1, 0, PWM_PERCENTAGE_TO_WIDTH(&PWMD1, 7500));
+  pwmEnableChannel(&PWMD1, 0, PWM_PERCENTAGE_TO_WIDTH(&PWMD1, 5000));
+  chThdSleepMilliseconds(5000);
+
+  /*
+   * Changes the PWM channel 0 to 25% duty cycle.
+   */
+  pwmEnableChannel(&PWMD1, 0, PWM_PERCENTAGE_TO_WIDTH(&PWMD1, 2500));
   chThdSleepMilliseconds(5000);
 
   /*
-   * Changes PWM period to half second and duty cycle to 50%.
+   * Changes PWM period to half second the duty cycle becomes 50%
+   * implicitly.
    */
   pwmChangePeriod(&PWMD1, 5000);
-  pwmEnableChannel(&PWMD1, 0, PWM_PERCENTAGE_TO_WIDTH(&PWMD1, 5000));
   chThdSleepMilliseconds(5000);
 
   /*
-   * Disables channel 0.
+   * Disables channel 0 and stops the drivers.
    */
   pwmDisableChannel(&PWMD1, 0);
   pwmStop(&PWMD1);
-- 
cgit v1.2.3