/****************************************************************************
* apps/examples/nunchuck/nunchuck_main.c
*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership. The
* ASF licenses this file to you 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.
*
****************************************************************************/
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <sys/ioctl.h>
#include <sys/param.h>
#include <stdio.h>
#include <stdlib.h>
#include <fcntl.h>
#include <errno.h>
#include <fixedmath.h>
#include <debug.h>
#include <unistd.h>
#include <nuttx/input/nunchuck.h>
/****************************************************************************
* Pre-processor Definitions
****************************************************************************/
/* Configuration ************************************************************/
#ifndef CONFIG_INPUT_NUNCHUCK
# error "CONFIG_NUNCHUCK is not defined in the configuration"
#endif
#ifndef CONFIG_EXAMPLES_NUNCHUCK_DEVNAME
# define CONFIG_EXAMPLES_NUNCHUCK_DEVNAME "/dev/nunchuck0"
#endif
#define FULL_RANGE 16
/****************************************************************************
* Private Function Prototypes
****************************************************************************/
static void show_buttons(nunchuck_buttonset_t oldset,
nunchuck_buttonset_t newset);
static void show_joystick(FAR const struct nunchuck_sample_s *sample);
static int nunchuck_read(int fd, FAR struct nunchuck_sample_s *sample);
static int nunchuck_calibrate(int fd);
/****************************************************************************
* Private Data
****************************************************************************/
/* The set of supported joystick buttons */
static nunchuck_buttonset_t g_nunchucksupported;
/* Last sampled button set */
static nunchuck_buttonset_t g_nunchucklast;
/* Calibration data */
static bool g_calibrated;
static bool g_lispositive;
static bool g_fispositive;
static int16_t g_xcenter;
static int16_t g_ycenter;
static b16_t g_xlslope;
static b16_t g_xrslope;
static b16_t g_yfslope;
static b16_t g_ybslope;
/* Joystick button names */
static const char *g_nunchucknames[NUNCHUCK_NBUTTONS] =
{
"FIRE", "SELECT",
};
/****************************************************************************
* Private Functions
****************************************************************************/
static void show_buttons(nunchuck_buttonset_t oldset,
nunchuck_buttonset_t newset)
{
nunchuck_buttonset_t chgset = oldset ^ newset;
int i;
if (chgset != 0)
{
/* Show each button state change */
for (i = 0; i <= NUNCHUCK_NBUTTONS; i++)
{
nunchuck_buttonset_t mask = (1 << i);
if ((chgset & mask) != 0)
{
FAR const char *state;
/* Get the button state */
if ((newset & mask) != 0)
{
state = "selected";
}
else
{
state = "released";
}
printf(" %-6s: %s\n", g_nunchucknames[i], state);
}
}
}
}
/****************************************************************************
* Private Functions
****************************************************************************/
static void show_joystick(FAR const struct nunchuck_sample_s *sample)
{
printf(" RAW: X=%d Y=%d\n", sample->js_x, sample->js_y);
if (g_calibrated)
{
int tmp;
int x;
int y;
tmp = sample->js_x - g_xcenter;
if ((g_lispositive && tmp >= 0) ||
(!g_lispositive && tmp < 0))
{
x = tmp * g_xlslope;
}
else
{
x = tmp * g_xrslope;
}
tmp = sample->js_y - g_ycenter;
if ((g_fispositive && tmp >= 0) ||
(!g_fispositive && tmp < 0))
{
y = tmp * g_yfslope;
}
else
{
y = tmp * g_ybslope;
}
printf(" Calibrated: X=%d Y=%d\n", x, y);
}
}
static int nunchuck_read(int fd, FAR struct nunchuck_sample_s *sample)
{
ssize_t nread;
/* Read the joystack sample */
nread = read(fd, sample, sizeof(struct nunchuck_sample_s));
if (nread < 0)
{
int errcode = errno;
fprintf(stderr, "ERROR: read() failed: %d\n", errcode);
return -errcode;
}
else if (nread != sizeof(struct nunchuck_sample_s))
{
fprintf(stderr, "ERROR: read() unexpected size: %ld vs %d\n",
(long)nread, sizeof(struct nunchuck_sample_s));
return -EIO;
}
#ifdef CONFIG_DEBUG_INPUT
/* Show the joystick position and set buttons accompanying the signal.
* Show the set of joystick buttons that we just read
*/
printf("Read position and button set\n");
show_joystick(sample);
show_buttons(g_nunchucklast, sample->nck_buttons);
#endif
usleep(10000);
return OK;
}
static b16_t nunchuck_slope(int16_t value, int32_t full_range)
{
return itob16(full_range) / (int32_t)value;
}
static int nunchuck_calibrate(int fd)
{
struct nunchuck_sample_s sample;
int ret;
printf("Calibrating the joystick...\n");
/* Get the center position */
printf("Center the joystick and press any button\n");
sample.nck_buttons = 0;
while (sample.nck_buttons == 0)
{
ret = nunchuck_read(fd, &sample);
if (ret < 0)
{
fprintf(stderr, "ERROR: nunchuck_read() failed: %d\n", errno);
return ret;
}
}
g_xcenter = sample.js_x;
g_ycenter = sample.js_y;
/* Wait release the button */
while (sample.nck_buttons != 0)
{
ret = nunchuck_read(fd, &sample);
if (ret < 0)
{
fprintf(stderr, "ERROR: nunchuck_read() failed: %d\n", errno);
return ret;
}
}
/* Get the left/right calibration data */
printf("Move the joystick to the far RIGHT and press any button\n");
while (sample.nck_buttons == 0)
{
ret = nunchuck_read(fd, &sample);
if (ret < 0)
{
fprintf(stderr, "ERROR: nunchuck_read() failed: %d\n", errno);
return ret;
}
}
g_lispositive = (sample.js_x > g_xcenter);
g_xlslope = nunchuck_slope(sample.js_x - g_xcenter, FULL_RANGE);
/* Wait release the button */
while (sample.nck_buttons != 0)
{
ret = nunchuck_read(fd, &sample);
if (ret < 0)
{
fprintf(stderr, "ERROR: nunchuck_read() failed: %d\n", errno);
return ret;
}
}
printf("Move the joystick to the far LEFT and press any button\n");
while (sample.nck_buttons == 0)
{
ret = nunchuck_read(fd, &sample);
if (ret < 0)
{
fprintf(stderr, "ERROR: nunchuck_read() failed: %d\n", errno);
return ret;
}
}
g_xrslope = nunchuck_slope(sample.js_x - g_xcenter, -FULL_RANGE);
/* Wait release the button */
while (sample.nck_buttons != 0)
{
ret = nunchuck_read(fd, &sample);
if (ret < 0)
{
fprintf(stderr, "ERROR: nunchuck_read() failed: %d\n", errno);
return ret;
}
}
/* Get the forward/backward calibration data */
printf("Move the joystick to the far FORWARD and press any button\n");
while (sample.nck_buttons == 0)
{
ret = nunchuck_read(fd, &sample);
if (ret < 0)
{
fprintf(stderr, "ERROR: nunchuck_read() failed: %d\n", errno);
return ret;
}
}
g_fispositive = (sample.js_y > g_ycenter);
g_yfslope = nunchuck_slope(sample.js_y - g_ycenter, FULL_RANGE);
/* Wait release the button */
while (sample.nck_buttons != 0)
{
ret = nunchuck_read(fd, &sample);
if (ret < 0)
{
fprintf(stderr, "ERROR: nunchuck_read() failed: %d\n", errno);
return ret;
}
}
printf("Move the joystick to the far BACKWARD and press any button\n");
while (sample.nck_buttons == 0)
{
ret = nunchuck_read(fd, &sample);
if (ret < 0)
{
fprintf(stderr, "ERROR: nunchuck_read() failed: %d\n", errno);
return ret;
}
}
g_ybslope = nunchuck_slope(sample.js_y - g_ycenter, -FULL_RANGE);
printf("Calibrated:\n");
g_calibrated = true;
printf(" X: center=%d, R-slope=%08lx L-slope=%08lx\n",
g_xcenter, g_xrslope, g_xlslope);
printf(" Y: center=%d, F-slope=%08lx B-slope=%08lx\n",
g_ycenter, g_yfslope, g_ybslope);
return OK;
}
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* nunchuck_main
****************************************************************************/
int main(int argc, FAR char *argv[])
{
int fd;
int tmp;
int ret;
int errcode = EXIT_FAILURE;
/* Reset some globals that might been been left in a bad state */
g_nunchucklast = 0;
/* Open the nunchuck device */
fd = open(CONFIG_EXAMPLES_NUNCHUCK_DEVNAME, O_RDONLY);
if (fd < 0)
{
fprintf(stderr, "ERROR: Failed to open %s: %d\n",
CONFIG_EXAMPLES_NUNCHUCK_DEVNAME, errno);
return EXIT_FAILURE;
}
/* Get the set of supported buttons */
ret = ioctl(fd, NUNCHUCKIOC_SUPPORTED, (unsigned long)((uintptr_t)&tmp));
if (ret < 0)
{
fprintf(stderr, "ERROR: ioctl(NUNCHUCKIOC_SUPPORTED) failed: %d\n",
errno);
goto errout_with_fd;
}
g_nunchucksupported = (nunchuck_buttonset_t)tmp;
printf("Supported joystick buttons:\n");
show_buttons(0, g_nunchucksupported);
/* Calibrate the joystick */
nunchuck_calibrate(fd);
for (; ; )
{
struct nunchuck_sample_s sample;
/* Wait for a signal and read the sample */
ret = nunchuck_read(fd, &sample);
if (ret < 0)
{
fprintf(stderr, "ERROR: nunchuck_read() failed: %d\n", errno);
goto errout_with_fd;
}
/* Show read sample */
show_joystick(&sample);
show_buttons(g_nunchucklast, sample.nck_buttons);
g_nunchucklast = sample.nck_buttons;
}
errcode = EXIT_SUCCESS;
errout_with_fd:
close(fd);
return errcode;
}