信息#

介绍 #

两台 VEX AIM 编程机器人可以连接起来，以便在项目进行过程中进行通信。消息传递方式允许一台机器人向另一台机器人发送消息。消息可以包含纯文本，也可以包含最多三个数字的文本。

接收到的消息会存储在先进先出（FIFO）队列中。这意味着最先接收到的消息将首先被读取。

Use is_message_available to check whether a message is ready to read. Then use get_message to read the next text message. If the message also includes numbers, use get_message_and_data to read the text and numbers together.

**注意：**要发送和接收消息，两个机器人必须已连接，并且两个机器人必须运行使用消息方法的项目。

以下是所有方法的列表：

操作——在机器人之间发送消息。

send_message — Sends text and up to three numbers to the linked robot.

获取器 — 读取消息或检查连接状态。

get_message — Returns the next received text message.
get_message_and_data — Returns the next received text message and numbers.
is_connected — Returns whether the robot is linked with another robot.
is_message_available — Returns whether a message is available to read.
get_name — Returns the name of the linked robot.

回调函数——当消息事件发生时运行函数。

handle_message — Runs a function when a specific message is received.
connected — Runs a function when the robot is linked with another robot.
disconnected — Runs a function when the robot is no longer linked with another robot.

行动 #

send_message #

send_message sends text and up to three numbers to the linked robot. Use this method on one robot when the other robot needs to receive a command, signal, or short piece of information. Send text by itself when the message is enough on its own. Add numbers when the message needs related values, such as sending “heading” with the robot’s current heading value.

On the receiving robot, use is_message_available to check that a message has arrived. Then use get_message for a text-only message, or get_message_and_data for a message that includes numbers.

Usage:
robot.link.send_message(message, arg1, arg2, arg3)

范围	描述
`message`	要发送给关联机器人的文本。
`arg1`	（可选）要随消息一起发送的数字。
`arg2`	（可选）要随消息一起发送的第二个号码。
`arg3`	可选。要随消息一起发送的第三个号码。

例子

机器人 1的代码

# Press the screen to tell Robot 2 which way to turn
robot.screen.print("Robot 1")

while not robot.screen.pressing():
    wait(5, MSEC)

robot.link.send_message("right")

机器人 2的代码

# Turn in the direction that Robot 1 sends
robot.screen.print("Robot 2")

while not robot.link.is_message_available():
    wait(5, MSEC)

direction = robot.link.get_message()

if direction == "left":
    robot.turn_for(LEFT, 90)
elif direction == "right":
    robot.turn_for(RIGHT, 90)

# Robot 1: continuously send the current heading to Robot 2
robot.screen.print("Robot 1")

while True:
    robot.link.send_message("heading", robot.inertial.get_heading())
    wait(50, MSEC)

# Robot 2: turn to match Robot 1's heading
robot.screen.print("Robot 2")

while True:
    if robot.link.is_message_available():
        message, heading = robot.link.get_message_and_data()
        robot.turn_to(heading)

    wait(50, MSEC)

吸气剂 #

get_message #

get_message returns the next received text message from the message queue. Use this method on the receiving robot when the linked robot sent a text-only message. A common order is to use is_message_available to check that a message has arrived, then use get_message before displaying, comparing, or using the returned text in another method.

Use send_message on the other robot to send a text-only message.

Usage:
robot.link.get_message(timeout)

范围	描述
`timeout`	Optional. The maximum time, in milliseconds, to wait for a message before continuing. The default is `1000`.

例子

机器人 1的代码

# Press the screen to send a message to Robot 2
robot.screen.print("Robot 1")

while not robot.screen.pressing():
    wait(5, MSEC)

robot.link.send_message("Hello, Robot 2!")

机器人 2的代码

# Display the message sent by Robot 1
robot.screen.print("Robot 2")
robot.screen.next_row()

while not robot.link.is_message_available():
    wait(5, MSEC)

message = robot.link.get_message()
robot.screen.print(message)

get_message_and_data #

get_message_and_data returns the next received text message and numbers from the message queue as a tuple. Use this method on the receiving robot when the linked robot sent text with one or more numbers. A common order is to use is_message_available to check that a message has arrived, then use get_message_and_data before using the returned text and numbers.

Use send_message on the other robot to send the text and numbers together.

Usage:
robot.link.get_message_and_data(timeout)

范围	描述
`timeout`	Optional. The maximum time, in milliseconds, to wait for a message before continuing. The default is `1000`.

例子

机器人 1的代码

# Continuously send the current heading to Robot 2
robot.screen.print("Robot 1")

while True:
    robot.link.send_message("heading", robot.inertial.get_heading())
    wait(50, MSEC)

机器人 2的代码

# Turn to match Robot 1's heading
robot.screen.print("Robot 2")

while True:
    if robot.link.is_message_available():
        message, heading = robot.link.get_message_and_data()
        robot.turn_to(heading)

    wait(50, MSEC)

is_connected #

is_connected returns whether the robot is linked with another robot. Use this method before sending or waiting for messages if the project needs to check that the robot-to-robot connection is ready.

True — The robot is linked with another robot.
False — The robot is not linked with another robot.

Usage:
robot.link.is_connected()

参数	描述
	该方法没有参数。

# Display whether the robot is connected
while True:
    robot.screen.clear_screen()
    robot.screen.set_cursor(1, 1)
    robot.screen.print(robot.link.is_connected())
    wait(50, MSEC)

is_message_available #

is_message_available returns whether a message is waiting in the message queue. Use this method before get_message or get_message_and_data so the receiving robot only tries to read a message after one has arrived.

True — There is a message available to be read.
False — There are no messages available to be read.

Usage:
robot.link.is_message_available()

参数	描述
	该方法没有参数。

例子

机器人 1的代码

# Press the screen to send a message to Robot 2
robot.screen.print("Robot 1")

while not robot.screen.pressing():
    wait(5, MSEC)

robot.link.send_message("Hello, Robot 2!")

机器人 2的代码

# Wait until a message is available, then display it
robot.screen.print("Robot 2")
robot.screen.next_row()

while not robot.link.is_message_available():
    wait(5, MSEC)

message = robot.link.get_message()
robot.screen.print(message)

get_name #

get_name returns the name of the linked robot. Use this method to show which robot is connected before sending or receiving messages. If no robot is linked, this method returns None.

Usage:
robot.link.get_name()

参数	描述
	该方法没有参数。

# Display the name of the linked robot
robot.screen.print(robot.link.get_name())

回调 #

handle_message #

handle_message registers a function that runs when the robot receives a specific text message. Use this method when the robot should respond automatically to a known message instead of checking the message queue in a loop. Define the callback function first, then register it with handle_message and the message text to watch for.

Usage:
robot.link.handle_message(callback, message)

范围	描述
`callback`	A previously defined function that runs when the received message matches `message`.
`message`	用于核对收到的消息的文本。

例子

机器人 1的代码

# Press the screen to send "smile" to Robot 2
robot.screen.print("Robot 1")

while not robot.screen.pressing():
    wait(5, MSEC)

robot.link.send_message("smile")

机器人 2的代码

# Show a happy emoji when Robot 1 sends "smile"
def robot_smile():
    robot.screen.show_emoji(HAPPY)

robot.link.handle_message(robot_smile, "smile")

while True:
    wait(50, MSEC)

connected #

connected registers a function that runs when the robot is linked with another robot. Use this method when the project should respond as soon as the robot-to-robot connection is made. Define the callback function first, then register it with connected.

Usage:
robot.link.connected(callback, args)

范围	描述
`callback`	预先定义的函数，当机器人与其他机器人连接时运行。
`args`	可选。包含要传递给回调函数的参数的元组。更多信息请参阅使用带参数的函数。

# Show a happy emoji when connected
def robot_smile():
    robot.screen.show_emoji(HAPPY)

robot.link.connected(robot_smile)

disconnected #

disconnected registers a function that runs when the robot is no longer linked with another robot. Use this method when the project should respond as soon as the robot-to-robot connection is lost. Define the callback function first, then register it with disconnected.

Usage:
robot.link.disconnected(callback, args)

范围	描述
`callback`	预先定义的函数，当机器人不再与其他机器人连接时运行。
`args`	可选。包含要传递给回调函数的参数的元组。更多信息请参阅使用带参数的函数。

# Show a sad emoji when disconnected
def robot_sad():
    robot.screen.show_emoji(SAD)

robot.link.disconnected(robot_sad)