diff options
Diffstat (limited to 'firmata.py')
| -rwxr-xr-x | firmata.py | 167 |
1 files changed, 167 insertions, 0 deletions
diff --git a/firmata.py b/firmata.py new file mode 100755 index 0000000..756c714 --- /dev/null +++ b/firmata.py @@ -0,0 +1,167 @@ +#! /usr/bin/env python + +""" +Python API for the Firmata protocol +Copyright (C) 2008 laboratorio (info@laboratorio.us) + +This program is free software: you can redistribute it and/or modify +it under the terms of the GNU General Public License as published by +the Free Software Foundation, either version 3 of the License, or +(at your option) any later version. + +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/>. +""" + +__version__ = "0.3" + +import time +import serial + +DIGITAL_MESSAGE = 0x90 # send data for a digital port +ANALOG_MESSAGE = 0xE0 # send data for an analog pin (or PWM) +REPORT_ANALOG = 0xC0 # enable analog input by pin # +REPORT_DIGITAL = 0xD0 # enable digital input by port +SET_PIN_MODE = 0xF4 # set a pin to INPUT/OUTPUT/PWM/etc +REPORT_VERSION = 0xF9 # report firmware version +SYSTEM_RESET = 0xFF # reset from MIDI +START_SYSEX = 0xF0 # start a MIDI SysEx message +END_SYSEX = 0xF7 # end a MIDI SysEx message + +# pin modes +INPUT = 0 +OUTPUT = 1 +PWM = 2 +SERVO = 3 + +LOW = 0 +HIGH = 1 +MAX_DATA_BYTES = 32 + +class Arduino: + + def __init__(self, port, baudrate=115200): + + self.serial = serial.Serial(port, baudrate, bytesize=8, timeout=2) + + self.wait_for_data = 0 + self.exec_multibyte_cmd = 0 + self.multibyte_channel = 0 + self.stored_input_data = [ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, \ + 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 ,0, 0, 0 ] + self.parsing_sysex = False + self.sysex_bytes_read = 0 + self.digital_output_data = [ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 ] + self.digital_input_data = [ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 ] + self.analog_input_data = [ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 ] + self.major_version = 0 + self.minor_version = 0 + self.__report() + + def __str__(self): + return "Arduino: %s" % self.serial.port + + def pin_mode(self, pin, mode): + """Setting mode to pin""" + self.serial.write(chr(SET_PIN_MODE)) + self.serial.write(chr(pin)) + self.serial.write(chr(mode)) + + def digital_read(self, pin): + """Reading from digital pin""" + return (self.digital_input_data[pin >> 3] >> (pin & 0x07)) & 0x01 + + def digital_write(self, pin, value): + """Writing to a digital pin""" + + port_number = (pin >> 3) & 0x0F + + if value == 0: + self.digital_output_data[port_number] = self.digital_output_data[port_number] & ~(1 << (pin & 0x07)) + else: + self.digital_output_data[port_number] = self.digital_output_data[port_number] | (1 << (pin & 0x07)) + + self.serial.write(chr(DIGITAL_MESSAGE | port_number)) + self.serial.write(chr(self.digital_output_data[port_number] & 0x7F)) + self.serial.write(chr(self.digital_output_data[port_number] >> 7)) + + def analog_read(self, pin): + """Reading from analog pin""" + return self.analog_input_data[pin] + + def analog_write(self, pin, value): + """Writing to a analog pin""" + self.serial.write(chr(ANALOG_MESSAGE | (pin & 0x0F))) + self.serial.write(chr(value & 0x7F)) + self.serial.write(chr(value >> 7)) + + def set_version(self, major, minor): + """Setting a minor and major version""" + self.major_version = major + self.minor_version = minor + + def available(self): + """Checking serial connection status""" + return self.serial.isOpen() + + def delay(self, secs): + """Waiting in seconds""" + time.sleep(secs) + + def parse(self): + """Preparing the data to be handled""" + data = self.serial.read() + if data != "": + self.__process(ord(data)) + + def __process(self, input_data): + """Handling input data""" + command = None + + if self.parsing_sysex: + if input_data == END_SYSEX: + self.parsing_sysex = False + else: + self.stored_input_data[self.sysex_bytes_read] = input_data + self.sysex_bytes_read += 1 + + elif self.wait_for_data > 0 and input_data < 128: + self.wait_for_data -= 1 + self.stored_input_data[self.wait_for_data] = input_data + + if self.exec_multibyte_cmd != 0 and self.wait_for_data == 0: + if self.exec_multibyte_cmd == DIGITAL_MESSAGE: + self.digital_input_data[self.multibyte_channel] = (self.stored_input_data[0] << 7) + self.stored_input_data[1] + elif self.exec_multibyte_cmd == ANALOG_MESSAGE: + self.analog_input_data[self.multibyte_channel] = (self.stored_input_data[0] << 7) + self.stored_input_data[1] + elif self.exec_multibyte_cmd == REPORT_VERSION: + self.set_version(self.stored_input_data[1], self.stored_input_data[0]) + else: + if input_data < 0xF0: + command = input_data & 0xF0 + self.multibyte_channel = input_data & 0x0F + else: + command = input_data # commands in the 0xF* range don't use channel data + + if command == DIGITAL_MESSAGE or \ + command == ANALOG_MESSAGE or \ + command == REPORT_VERSION: + self.wait_for_data = 2 + self.exec_multibyte_cmd = command + + def __report(self): + """Reporting analog and digital pins""" + + self.delay(2) + for port in range(6): + self.serial.write(chr(REPORT_ANALOG | port)) + self.serial.write(chr(1)) + + for port in range(2): + self.serial.write(chr(REPORT_DIGITAL | port)) + self.serial.write(chr(1)) |