Importing The Package And Instantiating The Library

Importing

To import this package, the standard import string is:

from telemetrix_rpi_pico_w import telemetrix_rpi_pico_w

Here is an example of instantiating the library and blinking the board LED until the user enters Control-C to end the application.

import sys
import time
from telemetrix_rpi_pic_w import telemetrix_rpi_pico_w

# The GPIO pin number for the built-in LED
BOARD_LED = 32

# LED States
ON = 1
OFF = 0

# instantiate the library
# You must specify the IP address assigned to the Pico W server.

board = telemetrix_rpi_pico_w.TelemetrixRpiPicoW(ip_address='192.168.1.133')

# Set the DIGITAL_PIN as an output pin
board.set_pin_mode_digital_output(BOARD_LED)

try:
    while True:
        # turn led on
        board.digital_write(BOARD_LED, ON)
        time.sleep(1)
        # turn led off
        board.digital_write(BOARD_LED, OFF)
        time.sleep(1)

except KeyboardInterrupt:
    board.shutdown()
    sys.exit(0)

To exit your application cleanly, you should always call the shutdown method.

The init Method

When instantiating the library, you can accept all the default parameters for most applications. However, you must specify the IP address assigned to the Pico W server.

board = telemetrix_rpi_pico_w.TelemetrixRpiPicoW(ip_address='192.168.1.133')

Several parameters offered by the __init__ method allow for some additional control.

def __init__(self, ip_address=None,
                 ip_port=31335,
                 sleep_tune=0.000001,
                 shutdown_on_exception=True,
                 reset_on_shutdown=True):

        """

        :param ip_address: IP address assigned to the Pico W

        :param ip_port: IP Port number.

        :param sleep_tune: A tuning parameter (typically not changed by user)

        :param shutdown_on_exception: call shutdown before raising
                                      a RunTimeError exception, or
                                      receiving a KeyboardInterrupt exception

        :param reset_on_shutdown: Reset the board upon shutdown

Let's take a look at these parameters.

ip_address

This mandatory parameter must be set to the IP address assigned to the Pico W server.

ip_port

The ip_port value must be the same for both the client and the Pico W server. Typically, this value is accepted as is. If you change the value from the default, you must compile a matching value in the Pico W server.

sleep_tune

This parameter is the sleep value expressed in seconds and is used at several strategic points in the client. For example, the serial receiver continuously checks the serial port receive buffer for an available character to process. If there is no character in the buffer, the client sleeps for the sleep_tune period before checking again.

Typically, you would accept the default value.

shutdown_on_exception

When this parameter is set to True, the library shutdown method is automatically called when an exception is detected, and all reporting is disabled.

By setting this parameter to False, the Pico W may continue to send data to your application even after restarting it.

The default is True and is recommended to be used.

reset_on_shutdown

When set to True (the default), this parameter will send a message to the Pico W to reset itself. After resetting, the Pico W board LED will stay lit until a connection is made with your router.