Example 4: Change PWM Frequency for 180 Degree Servo

examples/ex4_change_pwm_frequency_180_deg_servo.py
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#-----------------------------------------------------------------------
# Pi Servo Hat - Example 4
#-----------------------------------------------------------------------
#
# Written by  SparkFun Electronics, June 2019
# Author: Wes Furuya
#
# Compatibility:
#     * Original: https://www.sparkfun.com/products/14328
#     * v2: https://www.sparkfun.com/products/15316
# 
# Do you like this library? Help support SparkFun. Buy a board!
# For more information on Pi Servo Hat, check out the product page
# linked above.
#
# 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/>.
#
#=======================================================================
# Copyright (c) 2019 SparkFun Electronics
#
# Permission is hereby granted, free of charge, to any person obtaining
# a copy of this software and associated documentation files (the
# "Software"), to deal in the Software without restriction, including
# without limitation the rights to use, copy, modify, merge, publish,
# distribute, sublicense, and/or sell copies of the Software, and to
# permit persons to whom the Software is furnished to do so, subject to
# the following conditions:
#
# The above copyright notice and this permission notice shall be
# included in all copies or substantial portions of the Software.
#
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
# EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
# MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
# IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
# CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
# TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
# SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
#=======================================================================

"""
This example should be used with a 180 degree (range of rotation) servo
on channel 0 of the Pi Servo Hat.

The extended code (commented out), at the end of the example could be
used to test the full range of the servo motion. However, users should
be wary as they can damage their servo by giving it a position outside
the standard range of motion.
"""

import pi_servo_hat
import time

# Initialize Constructor
test = pi_servo_hat.PiServoHat()

# Restart Servo Hat (in case Hat is frozen/locked)
test.restart()

# Test Run
#########################################
# Moves servo position to 0 degrees (1ms), Channel 0
test.move_servo_position(0, 0, 180)

# Pause 1 sec
time.sleep(1)

# Moves servo position to 180 degrees (2ms), Channel 0
test.move_servo_position(0, 180, 180)

# Pause 1 sec
time.sleep(1)

# 50 Hz Test
#########################################
# Set PWM Frequency to 50 Hz
test.set_pwm_frequency(50)

# Sweep from 0 to 180 degrees and back
for i in range(0, 180):
    print("Input: ", end = '')
    print(i, end = '')
    test.move_servo_position(0, i, 180)
    print(" Estimated Pos: ", end = '')
    print(test.get_servo_position(0, 180))
    time.sleep(.01)
for i in range(180, 0, -1):
    print("Input: ", end = '')
    print(i, end = '')
    test.move_servo_position(0, i, 180)
    print(" Estimated Pos: ", end = '')
    print(test.get_servo_position(0, 180))
    time.sleep(.01)


# 100 Hz Test
#########################################
# Set PWM Frequency to 100 Hz
test.set_pwm_frequency(100)

# Sweep from 0 to 180 degrees and back
for i in range(0, 180):
    print("Input: ", end = '')
    print(i, end = '')
    test.move_servo_position(0, i, 180)
    print(" Estimated Pos: ", end = '')
    print(test.get_servo_position(0, 180))
    time.sleep(.05)
for i in range(180, 0, -1):
    print("Input: ", end = '')
    print(i, end = '')
    test.move_servo_position(0, i, 180)
    print(" Estimated Pos: ", end = '')
    print(test.get_servo_position(0, 180))
    time.sleep(.05)


# 200 Hz Test
#########################################
# Set PWM Frequency to 200 Hz
test.set_pwm_frequency(200)

# Sweep from 0 to 180 degrees and back
for i in range(0, 180):
    print("Input: ", end = '')
    print(i, end = '')
    test.move_servo_position(0, i, 180)
    print(" Estimated Pos: ", end = '')
    print(test.get_servo_position(0, 180))
    time.sleep(.05)
for i in range(180, 0, -1):
    print("Input: ", end = '')
    print(i, end = '')
    test.move_servo_position(0, i, 180)
    print(" Estimated Pos: ", end = '')
    print(test.get_servo_position(0, 180))
    time.sleep(.05)