I am creating a GUI with PyQT4 on Python 3. I however am trying to setup a serial port using PySerial that I can later implement into this GUI. I don't know how to view if the command being sent is what I want so is there a program I can use to see the correct bytes are being sent?
To be more clear: I want to see the BYTES being sent or received.
Use pyserial's read and write methods to check what you're receiving from the peripheral and what you're sending to it. You could optionally use the method to_bytes to dig deeper, even though most serial devices accept only ASCII commands.
Also, the Serial class has builtin logging, you only need to enable it.
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I have an app that communicates with a bluetooth device, and I'm trying to replace that app with some code.
I tried using C# InTheHand nuget, Microsoft's Bluetooth LE Explorer, python's sockets and others to send data and see what happens.
But there's something I still don't understand - in each way using different libraries I saw in wireshark a different protocol: ATT, RFCOMM, L2CAP...
When I sniffed my bluetooth traffic from my phone using the app mentioned before, I saw mostly HCI_CMD protocol traffic.
How can I choose the protocol I want to send? Is there a simple package for that? something to read?
Do I need to build the packet myself? including headers and such?
Thank you!
Update:
Using Microsoft's Bluetooth LE Explorer I was able to send a packet that lit up my lamp, starting with 02010e10000c00040012(data)
Using bleak I was able to send a packet starting with 02010e10000c00040052(data)
the difference makes the lamp not ligh up and I'm not sure if I can change it via bleak as it's not part of the data I send
I think what you are showing is that bleak does a write without response while MS BLE Explorer does a write_with_response.
Looking at the Bleak documentation for write_gatt_char that seems to be consistent as response is False by default
write_gatt_char Parameters:
char_specifier (BleakGATTCharacteristic, int, str or UUID). The characteristic to write to, specified by either integer handle, UUID
or directly by the BleakGATTCharacteristic object representing it.
data (bytes or bytearray) – The data to send.
response (bool) – If write-with-response operation should be done. Defaults to False.
I would expect the following to have the desired effect:
await client.write_gatt_char(LIGHT_CHARACTERISTIC, b"\x55\xaa\x03\x08\x02\xff\x00\xff\xf5", True)
I recently aquired a Segway Ninebot ES2 electric scooter. I can connect to the scooter via Bluetooth LE and grab information such as battery status, current mileage, temperature, and so on. This is all done through an application.
On my Android device, I've successfully extraceted the HCI log file, which I imported into Wireshark. I can see all the requests and commands send back and forth between my phone and the scooter. However, the requests and responses are all garbage and I have no idea how to interpret them.
Example of a sent command (info says Sent Write Command, Handle: 0x000e (Nordic UART Service: Nordic UART Tx))
Example of the received value I got right after (info says Rcvd Handle Value Notification, Handle: 0x000b (Nordic UART Service: Nordic UART Rx))
How am I supposed to interpret these responses? If the battery status was 59%, I would expect it to return something like 0x3b (0x3b hex is 59 decimal). But honestly, I have no idea how this works. Maybe they're returning a bunch of data in a data type only their app knows how to interpret? Like JSON for web.
Here's an example from the nRF Connect for Mobile application, where I hit the down arrow on all the characteristics: https://i.imgur.com/hREDomP.jpg (large image)
And probably more important: How do I replicate a request or command in nRF Connect? I've tried sending a byte array that looks like 0x {02410011000d.....} (from the Write Command) in the application, but I have no idea how to read the response.
If someone is still interested, I did the same research for this scooter.
That's standart BLE communacation, device offers BLE "services" and "characteristics". Service can contain one or more characteristics, by which you communicate with device. Each charateristic can allow different types of interaction with it: writing into it, reading from it, subscribing to notifications (so you dont have to to manually read, it kinda pushes data to your app), and more (read here, for example)
Take a look at your wireshark screenshot: you can see Service UUID, Handle UUID (the characteristic), and handle ID. You can communicate with device via uuid or id, depending on your programming language or library (more about uuids).
In this particular scooter there are two characteristics, one allows writing into it, another - allows subscribing to it. Together, they act like RX and TX wires in UART: you write data into one and read from another. So, to begin communication with scooter you must establish connection to it, subscribe for notifications from one ch, and write data to another.
As for protocol: look again at she screenshots, "UART Tx" is the actual payload that was sent to scooter and "UART Rx" was the response. Yes, it's binary data, that only app would understand. Luckily, protocol has been reverse engineered and is well documented. In your example app requests serial number, and it's returned in response - "N2GWX...". In order to request battery percentage you must build another payload according to protocol.
I'm not sure if it's still relevant, but at least for those, who will be interested in the topic.
You can try the following to understand how to interpret response from the device.
An option to consider is to fetch manufacturer's mobile app (apk) either by adb or from sites like apkmirror, etc.
Then apply some reverse-eng tool like JADX.
If you're lucky and the code is somewhat readable, then search for smth that has to do with response (like ResponseParser) and try to find algo that is used to interpret the response.
However, the very first attemp should always be to search on github/google if smb did it already for your device, unless it's very niche.
I am creating and sending an SNMP packet manually using pcap.net, the reason for this is that I need to be able to change the sender details of the SNMP packet to one other than the application hosts NIC and which wouldn't be possible with the library unless I somehow intercepted the outgoing packet and changed the details on the fly. My issue is that I can send out my packet and receive it using pcap.net as well but I need a way to decode the BER encoded packet, can I directly decode a received packet without using the rest of the library? If so what function could I call so I can read the oid values directly from a recieved packet?
When you first asked this question I read it but could not provide much insight.
What #SNMP offers are the two set of functions below,
MessageFactory.ParseMessage, a few functions that parse raw bytes to ISnmpMessage.
ISnmpMessage.ToBytes, a method that generates raw bytes.
If you can write adapters to bridge #SNMP and Pcap.NET, you should be able to achieve what you want.
Next time, make sure you avoid C# tag, as yes you might be down voted due to that.
References:
http://help.sharpsnmp.com/html/Overload_Lextm_SharpSnmpLib_Messaging_MessageFactory_ParseMessages.htm
http://help.sharpsnmp.com/html/M_Lextm_SharpSnmpLib_Messaging_ISnmpMessage_ToBytes.htm
I have programmed a D-Link GSM modem on a windows machine to send and receive SMS, for testing I used Hyperterminal.
In windows the connection manager initiates the COMx ports, modem uses one unlisted COMx port through which I can send an SMS, and through a listed NMEA port I receive incoming SMS, calls like +CMTI: "ME", 11 or RING +CLIP: XXXXXXXXXXXX
I'm successfully interpreting the message and programming it to my requirements in windows. While trying the same in linux(Fedora), I see the modem initialises /dev/ttyUSB0 and /dev/ttyUSB1 as the two newly identified devices. I use minicom to set the device ports and communicate AT commands to the same.
In both the devices (/dev/ttyUSB0 and /dev/ttyUSB1) I'm not receiving unsolicited AT result code like +CMTI indication whenever I'm expecting a new SMS. FYI I've set the CNMI setting according to the manual and several other combinations.
A strange thing is that I'm able to see RING when I'm calling but not +CLIP: <callerinfo>. Similarly I'm not getting ++PSBEARER: XX, Y or +CMTI: "ME", XX
The only alternative solution is to poll the UNREAD messages at regular intervals, which is generally a bad design. Please tell me if I'm doing anything wrong with regards to the configuration, should I change some thing else apart from these?
RING is the only UR code you can assume that will always come without any specific configuration (just because this is such an old relic that it just behaves that way...). For all other UR codes, you must explicit enable each and every one of them, e.g. AT+CLIP=1, etc, otherwise they will not be enabled. And enabling those are per serial interface, e.g. running AT+CLIP=1 on /dev/ttyUSB0 will not make +CPLIP: ... be printed on /dev/ttyUSB1.
So when you get them on windows the connection manager, it must be because it has those included in it init strings. Minicom I think defaults to no init string or possibly just a very classical one like ATS0=0 E1Q0V1.
I want to a Java ME application that transfers any SMS received to a PC using bluetooth. The PC can then direct the Java ME application via bluetooth to send a response SMS. Is there library available for this architecture or I have to design it myself?
Is this approach correct or a better one exists? I want to use bluetooth as then I will not have dependency on the cable.
You'll need to create this yourself, however you'll find that you can't do what you want with J2ME.
J2ME can't access any old SMS that the handset receives, only ones sent to a specific port upon which the MIDlet is listening. So to get all the other SMSes, create a bluetooth serial/dial-up connection to your handset in the way I've described in this answer.
Create a PC client which repeatedly issues AT+CGML commands (as described in the AT command set document linked to in the answer above), to see when an SMS has been received. Use AT+CGMR to read and parse the message text. Then use AT+CGMS to sent a response. This can all be done over bluetooth.
It's better to use the serial connection to send a response, because a MIDlet cannot usually be triggered to open based on incoming bluetooth data.
Hope this helps.
You may have already achieved your task, anyway for the reference I think it is much better if you try using Gammu . I'm using it for the same task (Send / receive SMS through PC ) with a simple bat file I have written, works like a charm.
Anyway you don't need any J2me program for this.
Wammu takes care of making the connection to phone and sending AT commands.