I am using pyserial with AT command to query a Huawei USB modem k3565. Some commands such as ser.write(b'at+cimi\r\n') return the imsi of the career. But when I try to get the phone number with the code below. It returns an error. Could it be my modem or platform(ubuntu 17.04) or my code.
In [35]: ser.write(b'at+cusd=1, "*99#", 15\r\n')
Out[35]: 23
In [36]: ser.read_all()
Out[36]: '\r\nERROR\r\n'
Related
I am using a barcode scanner as part of a project, everything works correctly until I exit the program then I can't communicate anymore with the barcode scanner. This holds true for whatever program I'm running, be it one of my own or just using screen to monitor the transmissions. As soon as I exit, the only way to make the scanner work again is to unplug and replug.
The scanner (this one) is always mounted correctly (usually at /dev/ttyACM0) and communicates by SSI over USB CDC.
I’ve tried monitoring with pyserial’s miniterm and with screen /dev/ttyACM0 9600 but the same problem arises (f.e. screen just says [screen is terminating])
Mind you, everything works well on another computer so I believe it might be an issue with the Jetson rather than the scanner.
In the project I’m trying to run, I use pyserial to interact with the device. Here is an extract of the code to give you an idea of how I use it:
import serial
serial_port = "/dev/ttyACM0"
baud_rate = 9600
with serial.Serial(serial_port, baud_rate, timeout=0.1) as device_serial:
device_serial.flush()
while True:
try:
# read a line from the serial port
barcode_byte_string = device_serial.readline()
if len(barcode_byte_string) > 0:
# convert the byte string to a string and strip the newline character
barcode = barcode_byte_string.decode("utf-8").rstrip()
# publish the barcode to the topic
self.publish_barcode(barcode, serial_port)
except serial.SerialException as e:
# exit with error code 1. This will cause the application to be restarted.
sys.exit(1)
except Exception as e:
break
I am trying to use the Bluetooth library in python 3 to enable me to allow a robot I am making to communicate with my PC. I have created a Bluetooth server that uses MAC addresses. unfortunately I have hit a halt in my program on this line:
s.bind((hostMACAddress,port))
OSError: [WinError 10049] The requested address is not valid in its context
For some reason it does not seem to like the MAC address (I have checked over the MAC address several times now and it is definitely correct). Personally, I would rather not want to use python 2 as the robot I am using is only compatible with python 3 and by using python 2 the whole idea would not work.
"""
A simple Python script to receive messages from a client over
Bluetooth using Python sockets (with Python 3.3 or above).
"""
import socket
hostMACAddress = 'xx:xx:xx:xx:xx:xx' # The MAC address of a Bluetooth adapter on the server. The server might have multiple Bluetooth adapters.
port = 3 # 3 is an arbitrary choice. However, it must match the port used by the client.
backlog = 1
size = 1024
s = socket.socket(socket.AF_BLUETOOTH, socket.SOCK_STREAM, socket.BTPROTO_RFCOMM)
s.bind((hostMACAddress,port))
s.listen(backlog)
try:
client, address = s.accept()
while 1:
data = client.recv(size)
if data:
print(data)
client.send(data)
except:
print("Closing socket")
client.close()
s.close()
Here is the guide I have been following:
https://blog.kevindoran.co/bluetooth-programming-with-python-3/
These lines I have used alternatively to using MAC addresses (I am have tried using both):
hostIPAddress = "x.x.x.x"
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
s.bind((hostIPAddress,22))
Is there any posibility to read from virtual serial ports without mentioned error?
I'm trying to reach data sent from symbol/zebra barcode scanner li4278. Device is working in simple com port emulation mode and it's under /dev/usb/hiddev0 as serial port.
I'm sure that emulation works fine because CuteCom can read from it, and also this simple pyton script works too:
defaultDevice = '/dev/usb/hiddev0'
inDev = open(defaultDevice, 'rb')
while True:
inBytes = inDev.read(1)
for x in inBytes:
print(x)
But anytime I'm trying to read it using pyserial with such a minimal code like this:
with serial.Serial('/dev/usb/hiddev0', timeout=1) as ser:
x = ser.read()
print(x)
the same error occurs: termios.error: (22, 'Invalid argument'). It's like it can't read from virtual serial ports.
And no, setting args to rtscts=True, dsrdtr=True doesn't work.
I have the same '22, invalid argument' error.
Linux Mint 18, 64 bit, Python 3.7, pyserial 3.4.
Anyone knows what's the thing?
I am learning to add i2c devices in device tree of raspberry's kernel 4.4.8. After successful compilation of DT, raspberry pi is not allowing me to log in to board.
showing "ssh: connect to host 10.1.1.103 port 22: Connection refused".
I have linked dt sources below
DT Souce.
one by one, I tried adding in all following files.
in file bcm2708-rpi-b.dts line 93. (lm75#48).
in file bcm2708-rpi-b-plus.dts line no. 87.
in file bcm2708.dtsi line no. 44.
Please help me. Any help will be appreciated.
Thanks.
Followup question to this: permanent USB port names? (Linux)
On Windows the port names don't change between actual physical ports. They are along the lines of "COM3", "COM6", etc.
On Linux, if I plug one USB device first , it will be "ttyUSB0" and if I plug the same device second in any other physical port it will be "ttyUSB1". That won't work if I want to, say, have 2 Arduinos connected via Pyserial to the PC.
In the above answer I was shown a way to get an IP-like "serial name". How can I feed that to the PySerial class instead?
An example:
import serial
ser = serial.Serial(port = "/dev/USBNAME", baudrate=9600)
ser.close()
ser.open()
if ser.isOpen():
ser.write("test")