I'm trying to send a multiline sms from an application I am creating to my phone via telnet to a GSM modem. I would like the message to be output to my phone as shown below but cannot figure out how to add new lines within the message string so that the message is output to my phone as below. I cannot find much documentation on this either and the few character codes (\r\n) I tried either terminated the telnet command were they were displayed in my code or were showing in the SMS received on my phone.
Does anybody know what character code that would give me a new line without terminating the telnet command within the message string?
at*smsm2m= “441234567891
Pinging 192.168.0.31 with 32 bytes of data:
Reply from 192.168.0.31: bytes=32 time=3ms TTL=64<br>
Reply from 192.168.0.31: bytes=32 time=1ms TTL=64<br>
Reply from 192.168.0.31: bytes=32 time=1ms TTL=64<br>
Reply from 192.168.0.31: bytes=32 time=1ms TTL=64
Ping statistics for 192.168.0.31:
Packets: Sent = 4, Received = 4, Lost = 0 (0% loss),
Approximate round trip times in milli-seconds:
The server side of Telnet is typically just a regular shell so you can do the same things you'd do for embedded newlines as if you were typing at a command line. Try this:
echo -e "this\nhas\nmultiple\nlines" | program
(you may need to look up flags for the echo command on the server if it's not a GNU machine)
Related
I use the gpsd python library in order to read and parse the NMEA string recieved from the gps device. I would like to send some command to gps in order to fine tune the measurement rate, report rate and so on.
It is possible using the gpsd library or I must send the command with in other way?
According to 'gpsd' manual:
To send a binary control string to a specified device, write to the
control socket a '&', followed by the device name, followed by '=',
followed by the control string in paired hex digits.
So if you have gpsd service running as gpsd -F /var/run/gpsd.sock you can use the following code to send commands to the gps device:
import socket
import sys
# Create a socket
sock = socket.socket(socket.AF_UNIX, socket.SOCK_STREAM)
# Connect the socket to the port where the GPSD is listening
gpsd_address = '/var/run/gpsd.sock'
sock.connect(gpsd_address)
# #BSSL 0x01<CR><LF> - Set NMEA Output Sentence (GGA only)
# cmd = '#BSSL 0x01' + '\r\n'
# #RST<CR><LF> - RST - Reset
cmd = '#RST' + '\r\n'
message = '&/dev/ttyUSB1='
cmd_hex = cmd.encode('utf-8').hex()
print ('cmd_hex {}'.format(cmd_hex))
# cmd_hex 405253540d0a
message += cmd_hex
bin_message = message.encode('utf-8')
print ("bin message {}".format(bin_message))
# bin message b'&/dev/ttyUSB1=405253540d0a'
sock.sendall(bin_message)
data = sock.recv(16)
print ('received {}'.format(data))
# received b'OK\n'
sock.close()
In my case I am sending #RST command followed by CR, LF symbols.
I want to do mass erase on my msp430f2619 using bsl. I use software jump in my code to invoke bsl. I send 0x80, get 0x90 from BSL(ack). Then i send mass erase command and get 0x90 again. Then i power off my device, then i power on the device, then i send 0x80 and get 0x90, that means there was no mass erase operation.
Read command is not working too. I send password (0xFF 32 times), after that send rx command, then i get few coorect bytes, and then infinite raw of 0xff.
I think i miised something before jump to bsl, please give an example code, or step by step instruction on how to make software jump to bsl and make it work correctly.
If you are sending 0x80 only, then get back 0x90, this confirms you have entered into the BSL since this completes the required synchronization sequence (see section 2.1 of this document). You should not require the "RX password" command since the "Mass erase" command is not protected.
The next sequence after the synchronization is to send the desired command, which should be the "Mass erase". There is a format to each of the BSL commands called the data frame. You want to send the following data frame: eight mandatory bytes (note two dummy bytes), and two checksum bytes. Note the "Mass erase" command does not contain data bytes, but you need to calculate the checksum bytes. Here are the bytes to be sent to perform the mass erase:
80 18 04 04 dd dd 06 A5 CL CH
Where: dd = dummy bytes (any value accepted), CL = Checksum low, CH = Checksum high
After sending this data frame then you should receive the ACK (0x90) byte. Then power off the device.
I am wondering that how to generate massive packet-in messages to the controller to test the response time of SDN controller in the environment of Mininet.
Can you give me some advice on it?
You could use iperf to send packets, like this:
$ iperf -c -F
You could specify the amount of time:
$IPERF_TIME (-t, --time)
The time in seconds to transmit for. Iperf normally works by repeatedly sending an array of len bytes for time seconds. Default is 10 seconds. See also the -l and -n options.
Here is a nice reference for iperf: https://iperf.fr/.
If you would like to use Scapy, try this:
from scapy.all import IP, TCP, send
data = "University of Network blah blah"
a = IP(dst="129.132.2.21")/TCP()/data
send(a)
I have a wireshark capture that contains an RTP multicast stream (plus some other incidental data).
Using a Tshark command like the following, I can produce a CSV of the RTP timestamp compared with the packet capture time:
tshark.exe -r "capture.pcap" -Eseparator=, -Tfields -e rtp.timestamp -e frame.time_epoch -d udp.port==5000,rtp
This decodes the UDP packets as RTP, and successfully prints out the two fields as expected.
Now, my question: The payload of the RTP stream is an MPEG2 Transport Stream, and I also want to print the PCR value (if there is one) alongside the packet and RTP timestamps.
In wireshark, I can see the PCR being decoded correctly, however using a command like the following:
tshark.exe -r "HBO HD CZ.pcap" -Eseparator=,-Tfields -e rtp.timestamp -e frame.time_epoch -e mp2t.af.pcr -d udp.port==5000,mp2t
...only prints out a "1" if there is a PCR oresent, not the actual value. I have also checked the .pcr_flag to confirm that these two are not exchanged, but still I see the same result.
The documentation seems to call mp2t.af.pcr a "Label", does this mean that Tshark is not able to use it as a field? Is there a way to generate a CSV with these values?
(What part of the documentation calls it a "Label"? That's a somewhat odd description of a named field.)
The problem is that the value that Wireshark displays after "base(XXX)*300 + ext(YYY)" is calculated and displayed, but the field itself isn't given an integral type and is instead given a type that doesn't have a value. Arguably, it should be an FT_UINT64 field and should be given a value, so that you can filter on it and can print the value in TShark.
Please file an enhancement request for this on the Wireshark Bugzilla.
I am using Telit modem GL 868 Dual V3. AT command AT#SCFG has 2 parameters- packet size to be used and data sending time-out for TCP. Is there any AT command which specifies that if any delimiter string is found, then that data will be sent on TCP ignoring the packet size and time-out?
There are commands #PADFWD, #PADCMD which serves the purpose of delimiter.
Below is a snapshot from AT commands reference guide for telit modem.