# nxt.direct module -- LEGO Mindstorms NXT direct telegrams # Copyright (C) 2006, 2007 Douglas P Lau # Copyright (C) 2009 Marcus Wanner # # 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. 'Use for direct communication with the NXT ***EXTREMELY ADVANCED USERS ONLY***' def _create(opcode, need_reply = True): 'Create a simple direct telegram' from telegram import Telegram return Telegram(True, opcode, need_reply) def start_program(opcode, fname): tgram = _create(opcode) tgram.add_filename(fname) return tgram def _parse_simple(tgram): tgram.check_status() def stop_program(opcode): return _create(opcode) def play_sound_file(opcode, loop, fname): tgram = _create(opcode, False) tgram.add_u8(loop) tgram.add_filename(fname) return tgram def play_tone(opcode, frequency, duration): 'Play a tone at frequency (Hz) for duration (ms)' tgram = _create(opcode, False) tgram.add_u16(frequency) tgram.add_u16(duration) return tgram def set_output_state(opcode, port, power, mode, regulation, turn_ratio, run_state, tacho_limit): tgram = _create(opcode, False) tgram.add_u8(port) tgram.add_s8(power) tgram.add_u8(mode) tgram.add_u8(regulation) tgram.add_s8(turn_ratio) tgram.add_u8(run_state) tgram.add_u32(tacho_limit) return tgram def set_input_mode(opcode, port, sensor_type, sensor_mode): tgram = _create(opcode, False) tgram.add_u8(port) tgram.add_u8(sensor_type) tgram.add_u8(sensor_mode) return tgram def get_output_state(opcode, port): tgram = _create(opcode) tgram.add_u8(port) return tgram def _parse_get_output_state(tgram): tgram.check_status() port = tgram.parse_u8() power = tgram.parse_s8() mode = tgram.parse_u8() regulation = tgram.parse_u8() turn_ratio = tgram.parse_s8() run_state = tgram.parse_u8() tacho_limit = tgram.parse_u32() tacho_count = tgram.parse_s32() block_tacho_count = tgram.parse_s32() rotation_count = tgram.parse_s32() return (port, power, mode, regulation, turn_ratio, run_state, tacho_limit, tacho_count, block_tacho_count, rotation_count) def get_input_values(opcode, port): tgram = _create(opcode) tgram.add_u8(port) return tgram def _parse_get_input_values(tgram): tgram.check_status() port = tgram.parse_u8() valid = tgram.parse_u8() calibrated = tgram.parse_u8() sensor_type = tgram.parse_u8() sensor_mode = tgram.parse_u8() raw_ad_value = tgram.parse_u16() normalized_ad_value = tgram.parse_u16() scaled_value = tgram.parse_s16() calibrated_value = tgram.parse_s16() return (port, valid, calibrated, sensor_type, sensor_mode, raw_ad_value, normalized_ad_value, scaled_value, calibrated_value) def reset_input_scaled_value(opcode, port): tgram = _create(opcode) tgram.add_u8(port) return tgram def message_write(opcode, inbox, message): tgram = _create(opcode) tgram.add_u8(inbox) tgram.add_u8(len(message) + 1) tgram.add_string(len(message), message) tgram.add_u8(0) return tgram def reset_motor_position(opcode, port, relative): tgram = _create(opcode) tgram.add_u8(port) tgram.add_u8(relative) return tgram def get_battery_level(opcode): return _create(opcode) def _parse_get_battery_level(tgram): tgram.check_status() millivolts = tgram.parse_u16() return millivolts def stop_sound_playback(opcode): return _create(opcode) def keep_alive(opcode): return _create(opcode) def _parse_keep_alive(tgram): tgram.check_status() sleep_time = tgram.parse_u32() return sleep_time def ls_get_status(opcode, port): 'Get status of low-speed sensor (ultrasonic)' tgram = _create(opcode) tgram.add_u8(port) return tgram def _parse_ls_get_status(tgram): tgram.check_status() n_bytes = tgram.parse_u8() return n_bytes def ls_write(opcode, port, tx_data, rx_bytes): 'Write a low-speed command to a sensor (ultrasonic)' tgram = _create(opcode) tgram.add_u8(port) tgram.add_u8(len(tx_data)) tgram.add_u8(rx_bytes) tgram.add_string(len(tx_data), tx_data) return tgram def ls_read(opcode, port): 'Read a low-speed sensor value (ultrasonic)' tgram = _create(opcode) tgram.add_u8(port) return tgram def _parse_ls_read(tgram): tgram.check_status() n_bytes = tgram.parse_u8() contents = tgram.parse_string() return contents[:n_bytes] def get_current_program_name(opcode): return _create(opcode) def _parse_get_current_program_name(tgram): tgram.check_status() fname = tgram.parse_string() return fname def message_read(opcode, remote_inbox, local_inbox, remove): tgram = _create(opcode) tgram.add_u8(remote_inbox) tgram.add_u8(local_inbox) tgram.add_u8(remove) return tgram def _parse_message_read(tgram): tgram.check_status() local_inbox = tgram.parse_u8() n_bytes = tgram.parse_u8() message = tgram.parse_string() return (local_inbox, message[:n_bytes]) #TODO Add docstrings to all methods OPCODES = { 0x00: (start_program, _parse_simple,'Starts program execution on the NXT brick'), 0x01: (stop_program, _parse_simple, 'Stops program execution on the NXT brick'), 0x02: (play_sound_file, _parse_simple, 'Plays a sound file on the NXT brick.'), 0x03: (play_tone, _parse_simple, 'Plays a tone on the NXT brick'), 0x04: (set_output_state, _parse_simple, 'Sets the state of motor ports on the NXT brick'), 0x05: (set_input_mode, _parse_simple, 'Sets the state of sensor ports on the NXT brick'), 0x06: (get_output_state, _parse_get_output_state, 'Gets the state of motor ports on the NXT brick'), 0x07: (get_input_values, _parse_get_input_values, 'Gets the state of sensor ports on the NXT brick'), 0x08: (reset_input_scaled_value, _parse_simple), #TODO What does this method do? 0x09: (message_write, _parse_simple, 'Sends a message to the mailboxes on the NXT brick'), 0x0A: (reset_motor_position, _parse_simple, 'Resets tachometers on the NXT brick'), 0x0B: (get_battery_level, _parse_get_battery_level, 'Gets the voltage of the NXT battery'), 0x0C: (stop_sound_playback, _parse_simple, 'Stops the currently running sound file'), 0x0D: (keep_alive, _parse_keep_alive, 'Resets the standby timer on the NXT brick'), 0x0E: (ls_get_status, _parse_ls_get_status), #TODO What does this method do? 0x0F: (ls_write, _parse_simple), #TODO What does this method do? 0x10: (ls_read, _parse_ls_read), #TODO What does this method do? 0x11: (get_current_program_name, _parse_get_current_program_name, 'Gets the name of the currently running program'), 0x13: (message_read, _parse_message_read, 'Reads the next message sent from the NXT brick'), }