mirror of
https://github.com/portapack-mayhem/mayhem-firmware.git
synced 2024-12-14 12:08:40 +00:00
77 lines
3.2 KiB
Plaintext
Executable File
77 lines
3.2 KiB
Plaintext
Executable File
/*
|
|
ChibiOS/RT - Copyright (C) 2006,2007,2008,2009,2010,
|
|
2011,2012,2013 Giovanni Di Sirio.
|
|
|
|
This file is part of ChibiOS/RT.
|
|
|
|
ChibiOS/RT is free software; you can redistribute it and/or modify
|
|
it under the terms of the GNU General Public License as published by
|
|
the Free Software Foundation; either version 3 of the License, or
|
|
(at your option) any later version.
|
|
|
|
ChibiOS/RT is distributed in the hope that it will be useful,
|
|
but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
GNU General Public License for more details.
|
|
|
|
You should have received a copy of the GNU General Public License
|
|
along with this program. If not, see <http://www.gnu.org/licenses/>.
|
|
|
|
---
|
|
|
|
A special exception to the GPL can be applied should you wish to distribute
|
|
a combined work that includes ChibiOS/RT, without being obliged to provide
|
|
the source code for any proprietary components. See the file exception.txt
|
|
for full details of how and when the exception can be applied.
|
|
*/
|
|
|
|
/**
|
|
* @defgroup PWM PWM Driver
|
|
* @brief Generic PWM Driver.
|
|
* @details This module implements a generic PWM (Pulse Width Modulation)
|
|
* driver.
|
|
* @pre In order to use the PWM driver the @p HAL_USE_PWM option
|
|
* must be enabled in @p halconf.h.
|
|
*
|
|
* @section pwm_1 Driver State Machine
|
|
* The driver implements a state machine internally, not all the driver
|
|
* functionalities can be used in any moment, any transition not explicitly
|
|
* shown in the following diagram has to be considered an error and shall
|
|
* be captured by an assertion (if enabled).
|
|
* @dot
|
|
digraph example {
|
|
rankdir="LR";
|
|
node [shape=circle, fontname=Helvetica, fontsize=8, fixedsize="true", width="0.9", height="0.9"];
|
|
edge [fontname=Helvetica, fontsize=8];
|
|
uninit [label="PWM_UNINIT", style="bold"];
|
|
stop [label="PWM_STOP\nLow Power"];
|
|
ready [label="PWM_READY\nClock Enabled"];
|
|
uninit -> stop [label="pwmInit()"];
|
|
stop -> stop [label="pwmStop()"];
|
|
stop -> ready [label="pwmStart()"];
|
|
ready -> stop [label="pwmStop()"];
|
|
ready -> ready [label="pwmEnableChannel()\npwmDisableChannel()"];
|
|
}
|
|
* @enddot
|
|
*
|
|
* @section pwm_2 PWM Operations.
|
|
* This driver abstracts a generic PWM timer composed of:
|
|
* - A clock prescaler.
|
|
* - A main up counter.
|
|
* - A comparator register that resets the main counter to zero when the limit
|
|
* is reached. An optional callback can be generated when this happens.
|
|
* - An array of @p PWM_CHANNELS PWM channels, each channel has an output,
|
|
* a comparator and is able to invoke an optional callback when a comparator
|
|
* match with the main counter happens.
|
|
* .
|
|
* A PWM channel output can be in two different states:
|
|
* - <b>IDLE</b>, when the channel is disabled or after a match occurred.
|
|
* - <b>ACTIVE</b>, when the channel is enabled and a match didn't occur yet
|
|
* in the current PWM cycle.
|
|
* .
|
|
* Note that the two states can be associated to both logical zero or one in
|
|
* the @p PWMChannelConfig structure.
|
|
*
|
|
* @ingroup IO
|
|
*/
|