We usually see a barcode scanner connected to a POS(usually a computer) but now I want RP seats in between scanner and POS and read upc number to do some other work but don't know how to send read UPC to POS from RP.
How can I do that?
Workflow: barcode scanner reads upc and send it to RP and I do have the code on RP that read upc digits but now want to send the extracted upc number to POS and stuck there
It seems that you intend to physically insert a Raspberry Pi between the point-of-sale device and the barcode scanner to create a new workflow, but logically it just breaks the chain of communications.
It is not the era of legacy COM port communication that used the DSUB9 connector, but now it is connected by the USB protocol, so it is not possible to insert new functions by such means.
Rather than that, it is more realistic to modify the POS application to add new functions to the processing when barcode data is received.
If it's a method close to your idea, as mentioned above, change the barcode scanner to a model that physically connects with a DSUB9 connector, and set the application to use the corresponding COM port, Raspberry Pi Is it inserted in between like an RS232C line monitor?
Otherwise, the Raspberry Pi would have to behave like a barcode scanner at the USB protocol level, such as Vendor ID Product ID.
Related
I want to make a VoIP ATA (Analog Telephone Adapter) Device using Raspberry Pi, furthermore, I also want to add FXS ports to the Raspberry Pi. Kindly, tell me whether it is possible or not. If Yes, then how?
Here is the
Reference Link
This is probably possible, but not with the Pi alone.
You will need to design and build some external circuitry to convert between telephone line audio (which apparently runs at 48 volts) and audio signals which the Pi can produce. Also it looks like the Pi has no audio input, so you might need to either add a USB audio device or use an analog to digital converter that the Pi has to read the audio signal coming in from the phone line, if it can be polled fast enough.
You might have better luck with a board that has a real microphone jack on it already, instead of the Pi.
Then on the software side you need to attach the audio out, whatever you are using to get audio in, and any circuitry you need to open/close the circuit or send special ring voltages to your VoIP software of choice. Working out how to write that driver code is going to depend heavily on what physical circuit you actually build and what VoIP software you want to have talk to it.
That link above has a design for a line-level audio to phone audio conversion circuit which may help you get started. You could also take the circuitry part of the project over to the Electrical Engineering StackExchange site.
I have a Raspberry PI with two NFC readers attached. Problem is that the readers get different device numbers each time the system reboots or a reader is detached and attached again.
I therefore created udev rules that create a fixed device name depending on the physical port a device is attached to. E.g. plug in NFC reader in the upper left port leads always to /dev/nfc_a and plugged into the upper right port leads always to /dev/nfc_b.
How can I now configure libnfc to use these devices and report the device names such as /dev/nfc_a as a part of the reading? I am using Node-RED with node-red-contrib-nfc (https://github.com/hardillb/node-red-contrib-nfc) on top of libnfc. My ultimate goal is to safely distinguish the two readers within my Node-RED flow to act differently upon the readings.
I already found the "connstring" configuration but I don't know how to correctly set it for using /dev/nfc_a.
It's been a LONG time since I wrote this node, but looking back at the nodejs library it's based on (nfc) the output message should contain a field called deviceID which should indicate which NFC reader triggered the input.
When I run on my machine I get:
deviceID: 'pn53x_usb:001:005'
Where 001 is the USB bus id and 005 is the device ID, which matches up with the output from lsusb. These should stay static as long as the readers are always plugged into the same USB sockets.
I've been trying to figure out how to turn my Raspberry Pi into a USB to Bluetooth serial adapter. I want to be able to send data over Bluetooth to the Pi which has a USB thermal printer registered at /dev/usb/lp0.
Using only standard command line apps such as hciconfig, hcitool, rfcomm, and sdptool I have been able to see the Pi as visible, and pair to it from an Android tablet using a Bluetooth SPP app on the Store. However, the tablet disconnects immediately, and no data is sent. rfcomm listen /dev/rfcomm0 1 also waits for a connection forever.
I think I'm able to achieve what I need without custom code, using solely standard command line apps, but I'm not entirely sure. socat will likely be of use to finally connect the sockets.
Figures that I'd get it right after posting. To anyone else looking to do something similar:
Pair with bluez-simple-agent
Create your serial port channel with sdptool add --channel=x sp
Listen for a connection on that channel with sudo rfcomm listen /dev/rfcomm0 x
Cross the streams with socat /dev/rfcomm0 /dev/usb/lp0
Beautiful. It's all so simple now.
I'm looking for a list of receivers that are compatible with the Raspberry Pi. I am trying to get an idea of all the different methods of communication that the Raspberry Pi is currently able to pick up. So far, I know that there is at least one Pi-compatible instance of each of the following receivers on the market:
RF (Radio Frequency) receiver
IR (Infrared) receiver
Bluetooth receiver
Internet searches have yielded nothing so far. Can anyone add to this list? I'd like to know if there's a receiver that can pick up a magnetic field change (like the iPhone's Hall sensor) or a receiver that can pick up a frequency change, but I'm looking for anything to add to this list.
Thanks
http://elinux.org/RPi_VerifiedPeripherals
This is a list of all verified devices for the pi I found.
I have an external device that we manufacture that basically monitors 4 voltages, converts them to a 16 bit digital number then streams this info back to a PC every 100mS or so, using a serial over USB style chip. Basically a data logging system.
We would now like to collect this information on an iPhone and I am wondering what is the best way to get the data into the iPhone?
I am assuming there is no way we can physically connect directly to the iPhone dock connector as the protocol to do this is not available to iOS developers?
Obviously we could do it over a WiFi network but there will not always be one and we want to keep the external hardware fairly simple, i.e. no need for a computer or Wireless router etc.
If we add Bluetooth connectivity to our hardware would this work? I read that only 'Made for iPod' type Bluetooth devices will connect, in which case how can we achieve 'made for iPod' status? It would be relatively easy to add the necessary Bluetooth chips to get the system up and running.
In an ideal world we would like to do this without having to use a 3rd party interface.
I have been thinking about trying to digitise data as an audio signal – like a modem, and send it into the line input jack, but I don’t think it will be fast enough – this would be new territory for me.
Anyway all suggestions gratefully received!
Thanks!