AP_BoardConfig: board specific config library

used to control board specific parameters, such as PWM output count

libraries/AP_BoardConfig/AP_BoardConfig.cpp

+/// -*- tab-width: 4; Mode: C++; c-basic-offset: 4; indent-tabs-mode: nil -*-
+/*
+   This program 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.
+
+   This program 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/>.
+ */
+/*
+ *   AP_BoardConfig - board specific configuration
+ */
+
+
+#include <AP_HAL.h>
+#include <AP_Common.h>
+#include <AP_BoardConfig.h>
+
+#if CONFIG_HAL_BOARD == HAL_BOARD_PX4
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <unistd.h>
+#include <drivers/drv_pwm_output.h>
+
+#ifdef CONFIG_ARCH_BOARD_PX4FMU_V1
+#define BOARD_PWM_COUNT_DEFAULT 2
+#else
+#define BOARD_PWM_COUNT_DEFAULT 4
+#endif
+#endif
+
+extern const AP_HAL::HAL& hal;
+
+// table of user settable parameters
+const AP_Param::GroupInfo AP_BoardConfig::var_info[] PROGMEM = {
+#if CONFIG_HAL_BOARD == HAL_BOARD_PX4
+    // @Param: PWM_COUNT
+    // @DisplayName: PWM Count
+    // @Description: Number of auxillary PWMs to enable. On PX4v1 only 0 or 2 is valid. On Pixhawk 0, 2, 4 or 6 is valid.
+    // @Values: 0:No PWMs,2:Two PWMs,4:Four PWMs,6:Six PWMs
+    AP_GROUPINFO("PWM_COUNT",    0, AP_BoardConfig, _pwm_count, BOARD_PWM_COUNT_DEFAULT),
+#endif
+
+    AP_GROUPEND
+};
+
+
+void AP_BoardConfig::init()
+{
+#if CONFIG_HAL_BOARD == HAL_BOARD_PX4
+    /* configurre the FMU driver for the right number of PWMs */
+
+    // ensure only valid values are set, rounding up
+    if (_pwm_count > 6) _pwm_count.set(6);
+    if (_pwm_count < 0) _pwm_count.set(0);
+    if (_pwm_count == 1) _pwm_count.set(2);
+    if (_pwm_count == 3) _pwm_count.set(4);
+    if (_pwm_count == 5) _pwm_count.set(6);
+
+    int fd = open("/dev/px4fmu", 0);
+    if (fd == -1) {
+        hal.scheduler->panic("Unable to open /dev/px4fmu");
+    }
+    if (ioctl(fd, PWM_SERVO_SET_COUNT, _pwm_count.get()) != 0) {
+        hal.console->printf("RCOutput: Unable to setup alt PWM to %u channels\n", _pwm_count.get());  
+    }   
+    close(fd);
+#endif    
+}

libraries/AP_BoardConfig/AP_BoardConfig.h

+/// -*- tab-width: 4; Mode: C++; c-basic-offset: 4; indent-tabs-mode: nil -*-
+
+#ifndef __AP_BOARDCONFIG_H__
+#define __AP_BOARDCONFIG_H__
+
+#include <AP_HAL.h>
+#include <AP_Common.h>
+#include <AP_Param.h>
+
+class AP_BoardConfig
+{
+public:
+    // constructor
+    AP_BoardConfig(void)
+    {
+		AP_Param::setup_object_defaults(this, var_info);
+    };
+
+    void init(void);
+
+    static const struct AP_Param::GroupInfo var_info[];
+
+private:
+    AP_Int8 _pwm_count;
+};
+
+#endif // __AP_BOARDCONFIG_H__
+
+