1#!/usr/bin/env python 2 3# Author: Alex Tereschenko <alext.mkrs@gmail.com> 4# Copyright (c) 2015 Alex Tereschenko 5# 6# Permission is hereby granted, free of charge, to any person obtaining 7# a copy of this software and associated documentation files (the 8# "Software"), to deal in the Software without restriction, including 9# without limitation the rights to use, copy, modify, merge, publish, 10# distribute, sublicense, and/or sell copies of the Software, and to 11# permit persons to whom the Software is furnished to do so, subject to 12# the following conditions: 13# 14# The above copyright notice and this permission notice shall be 15# included in all copies or substantial portions of the Software. 16# 17# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, 18# EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF 19# MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND 20# NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE 21# LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION 22# OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION 23# WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE 24 25import mraa 26import sys 27 28sys.stdout.write("Initializing UART...") 29u=mraa.Uart(0) 30print("...done") 31 32print("Setting UART parameters: baudrate 115200, 8N1, no flow control") 33u.setBaudRate(115200) 34u.setMode(8, mraa.UART_PARITY_NONE, 1) 35u.setFlowcontrol(False, False) 36 37msg_b = bytearray("Hello, mraa byte array!", "ascii") 38print("Sending message as a byte array: '{0}'".format(msg_b)) 39u.write(msg_b) 40# Make sure the message gets out to the line. 41# It's generally unnecessary (and performance-degrading) to do this explicitly, 42# UART driver normally takes care of that, but it may be useful with specific 43# half-duplex endpoints, like Dynamixel servos. 44u.flush() 45 46msg_s = "Hello, mraa string!" 47print("Sending message as a string: '{0}'".format(msg_s)) 48u.writeStr(msg_s) 49 50sys.stdout.write("Two-way, half-duplex communication, sending a flag...") 51u.writeStr("X") 52print("...sent, awaiting response...") 53# Checking for data in the RX buffer, giving it a 100ms timeout 54if u.dataAvailable(100): 55 print("We've got a response: '{0}', says the other side".format(u.readStr(20))) 56else: 57 print("No data received, do you have anything at the other end?") 58