I have a few Raspberry Pi devices (b3+) running a telnet session to our server at work. Warehouse employees scan bar codes to move product through the warehouse. These Raspberry Pi devices are running Raspbian and have replaced handheld scanners (since the warehouse staff kept breaking them). These Pi devices boot up into the terminal and establish a telnet connection with the server.
The handheld scanners that were replaced by these Pi devices, provided an audio warning tone if something didn't scan correctly (we're assuming it was an ascii generation), which allowed users to be notified of the error. After bashing my head against the wall - and pretty much anything else I can find - I'm hoping someone here can help me out.
I'm looking for a way for the Pi to generate a warning sound while in the telnet session...using ascii 7 (I'm not sure if any text is returned when the error is received or not). The sound will need to be transmitted from the Pi to the display speakers via an HDMI connection. Any suggestions?
NOTE: We can get wav files to play off the Pi using the CLI...we just can't quite get ascii 7 to return a warning/beep.
Thanks
Related
Context:
I have a Raspberry Pi 4 sitting directly next to my iPhone. I have a bluetooth multisensor ~3 rooms away that I am able to connect to from my phone but I cannot reach it from my Raspberry Pi (verified via bluetoothctl) for home automation purposes with Home Assistant. When I bring the sensor in the same room as the iPhone and Raspberry Pi 4 I am able to receive data on both devices, but when I place it in its ideal location for my purposes, I am only able to reach it via iPhone.
Questions:
Is there a way that I am able to extend the Raspberry Pi Bluetooth range via terminal in anyway? I've already disabled WiFi in case that was causing any issues.
If not, is there a dongle I can add to the RP4 where I would be able to get an extended range?
I had a quick opinion question regarding a Raspberry Pi/Python based home security system I'm working on. My end goal is to have magnetic door/window sensors being monitored by a Raspberry Pi 4 server. If a window or door is opened while the system is armed it will play an alarm sound to the connected speakers. I would then have Raspberry Pi Zero W powered keypad panels (with LCD screens and a 12 digit keypad) that would allow me to see whether the system is armed or disarmed and allow me to input the passcode to arm or disarm the system. The Raspberry Pi Zero W panels would connect to the Raspberry Pi 4 server over the network.
I already have a somewhat functional test system running in a single Python script with everything connected to the Raspberry Pi 4 (link below). However, I'm now at a point where I need to figure out how to tie in the Raspberry Pi Zero W keypad panels I would like to integrate over the network. My question for you all is how would you go about implementing the network connectivity portion of this? Should I use something like Node.js with some kind of database? Perhaps the socket module in Python for something low-level? Something else entirely?
I'm up for any and all suggestions for how to go about this. Please let me know if you have any questions. Thanks in advance!
Poorly Done Diagram: https://imgur.com/a/AnAVzLt
Current Working Code: https://github.com/kevbo423/RPHSP/blob/master/Home_Security_System.py
If this was me, As you have the power of a full fat Pi 4, I would use a PHP web server on the "server" Pi that the other nodes POST to. This will give you the benefit of not having to deal with low level networking. You could also potentially add further devices or web services in the future with more integration opportunities.
You would then need to interface python to the PHP server however this could be done with a simple text file or alike.
I'm working on a project to control a drone using an EEG headset. The EEG headset is connected to my laptop [runnig ubuntu 18.04] and the drone to the raspberry pi [raspbian].
The code for processing the EEG data on the laptop as well as the code to control the drone is written on python 3.6 and work without any problems.
setup:
the EEG headset[ neurosky mindwave mobile 2] and the drone[ parrot mambo] both use BLE[bluetooth low energy] to connect with the devices. since both of them use Bluetooth it would be hard to send and receive data simultaneously to both the devices using a single code and laptop as they require a continuous uninterrupted connection and high data rates. hence the EEG headset is connected to the laptop via BLE and similarly the drone to the raspberry pi 3b+. The laptop takes care of processing the EEG signal and determining the desired command, while the raspberry pi acts as a wireless controller for the drone.
system setup
I need to pass the values between these 2 codes[and devices] so as to control the drone using the EEG signal. For eg, if I want to make the drone go forward after processing the signal I need to send say "1" or "f" to the raspberry pi from the laptop.
A wired connection such as Ethernet cable or USB is preferred over a wireless method.
The data size and rate is very less as a single character is sufficient and it will be sent only once every few seconds.
Which would be the best method to achieve this sort of communication
Use kafka or 0mq to loosely couple the laptop sender to the rasp pi receiver.
If one of them reboots, that's ok, the other will keep plugging away.
In the kafka case, you will enjoy the advantage of being able to replay a laptop publisher session again and again as you tweak and test the rasp pi client code.
Hello my name is Edris,
I am looking to make a connection between a raspberry and 2 arduino's with bluetooth. So the raspberry pi 3 would be the master and the arduino's slaves.
But then I thought mayby is it easier to have two connections at the same time.
So one with the build in bluetooth chip
and the other
with a usb bluetooth stick.
The bluetooth chips are all BLUE LoW Energy. Also the build in chip in the raspberry pi 3
Looking forward to hear from someone.
Edris
here are a couple of ways to connect
my preference is bluetoothctl. you'll be able to control each dongle by it's ID, given its ID appears when you do scan on and a list of IDs prints
I have a 20 year old device that prints data through a 1994 HP Deskjet 550c printer using a parallel port. Now the printer is broken and so there's no way to view the device output. I was thinking of hooking the parallel port from the device to a Raspberry Pi 3 which will display the data on a computer screen. I can get a parallel to USB cable which connects the old device to the Raspberry Pi. When I press the print button on the device, data should be sent to the Pi, but what I'm worried about is the format of the data. Is there a standard protocol for print data, or does every printer manufacturer use their own protocol? Do you know of any open sourced python scripts that can directly parse the print data coming from the usb port? Do I need to install any drivers on the Pi?