esp-idf/tools/idf_monitor_base/serial_reader.py

104 wiersze
4.2 KiB
Python

# Copyright 2015-2021 Espressif Systems (Shanghai) CO LTD
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
import sys
import time
import serial
from .constants import TAG_SERIAL
from .output_helpers import red_print, yellow_print
from .stoppable_thread import StoppableThread
try:
import queue
except ImportError:
import Queue as queue # type: ignore # noqa
class SerialReader(StoppableThread):
""" Read serial data from the serial port and push to the
event queue, until stopped.
"""
def __init__(self, serial_instance, event_queue):
# type: (serial.Serial, queue.Queue) -> None
super(SerialReader, self).__init__()
self.baud = serial_instance.baudrate
self.serial = serial_instance
self.event_queue = event_queue
self.gdb_exit = False
if not hasattr(self.serial, 'cancel_read'):
# enable timeout for checking alive flag,
# if cancel_read not available
self.serial.timeout = 0.25
def run(self):
# type: () -> None
if not self.serial.is_open:
self.serial.baudrate = self.baud
# We can come to this thread at startup or from external application line GDB.
# If we come from GDB we would like to continue to run without reset.
if self.gdb_exit is False:
# This sequence of DTR/RTS and open/close set the serial port to
# condition when GDB not make reset of the target by switching DTR/RTS.
self.serial.rts = True # IO0=LOW
self.serial.dtr = self.serial.dtr # usbser.sys workaround
self.serial.open()
self.serial.close()
self.serial.rts = False # IO0=HIGH
self.serial.dtr = False
else: # if we exit from GDB, we don't need to reset the target
self.serial.rts = False
self.serial.dtr = True
# Current state not reset the target!
self.gdb_exit = False
self.serial.open()
time.sleep(0.005) # Add a delay to meet the requirements of minimal EN low time (2ms for ESP32-C3)
self.serial.rts = False # Set rts/dtr to the working state
self.serial.dtr = self.serial.dtr # usbser.sys workaround
try:
while self.alive:
try:
data = self.serial.read(self.serial.in_waiting or 1)
except (serial.serialutil.SerialException, IOError) as e:
data = b''
# self.serial.open() was successful before, therefore, this is an issue related to
# the disapperence of the device
red_print(e)
yellow_print('Waiting for the device to reconnect', newline='')
self.serial.close()
while self.alive: # so that exiting monitor works while waiting
try:
time.sleep(0.5)
self.serial.open()
break # device connected
except serial.serialutil.SerialException:
yellow_print('.', newline='')
sys.stderr.flush()
yellow_print('') # go to new line
if data:
self.event_queue.put((TAG_SERIAL, data), False)
finally:
self.serial.close()
def _cancel(self):
# type: () -> None
if hasattr(self.serial, 'cancel_read'):
try:
self.serial.cancel_read()
except Exception: # noqa
pass