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rfid, xbee and raspberry pi

+1 vote
...Still no detailed response

Good day Sir ,

How do i send tag signals from a UHF UART RFID reader + USB dongle xbee(router) + Raspberry Pi2 - CLIENT NODE
to a Laptop USB Xbee dongle(Coordinator) -SERVER NODE


Hardware:


Raspberry Pi Model 2
WIFI DONGLE CONNECTED TO RASPBERRY PI
Cottonwood UART UHF READER
1 USB EXPLORER DONGLE XBEE SERIES 1 (CONNECTED TO LAPTOP_CONFIGURE AP1(2/WPPP) COORDINATOR
1 USB EXPLORER DONGLE XBEE SERIES 1 (CONNECTED TO USB PORT RASPBERRY) ROUTER
1 UHF COTTONWOOD RFID READER RX-TX CONNECTED TO TX-RX GPIO PIN

I want the RFID reader to scan Tags and transfer the tag through the xbee (router) and send the tag information to the xbee (coordinator) connected to the laptop end.

when the xbee (coordinator) recieves the tag information , it searches Mysql database on the laptop to retrieve USER PROFILE information that has been stored in the (database for that particular TagID) and send it back wirelessly through xbee(coordinator) to the xbee(router) on the Raspberry pi. The raspberry Pi screen then displays a webpage show the information recieved from the database.


This is my ultimate goal :

1) a user with a UHF RFID tag makes contact with a UHF RFID reader
(that is hooked up to a xbee pro series 1(router) and a Raspberry PI 2.


2)it send the tagid info to the xbee s1 usb laptop (coordinator )

3) xbee coordinator checks for tagid in my sql database and sends it back to the xbee (router) that is connected to the raspberry pi.

4)which causes it to trigger and display a text, webpage , video, audio on the Raspberry pi screen.
should wifi be used to transfer audio and video to the recieving raspberry, if so how do i go about it?

5)The text, video, webpage, audio, etc files are sent from a remote Laptop which acts as the Coordinator Xbee pro series 1. The Xbee is connected to the laptop using a USB Explorer Dongle. The Laptop on the other end is the Coordinator that is the Base Station.

Python ode for the uhf reader needs to be adjusted so it can continuously read tags.(pls help complete)

import as3992_api

def main():
ann = as3992_api.AntennaDevice()

print "Firmware info: %s\nHardware info: %s" % ann.get_system_info()

print "Activating antenna"
ann.set_antenna_state(True)

print "Tags:"
for epc, rssi in ann.iter_epc_rssi():
print epc.encode("HEX"), rssi

ann.set_antenna_state(False)

if __name__ == "__main__":
main()



Only using Python Programming Language.

Thank you in advance!
Code:
asked Oct 11, 2015 in RF Solutions and XBee by yomi New to the Community (1 point)

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1 Answer

+1 vote
I am confused. Why are you not simply connecting the RS232 port of the RFID reader to an RS232 version of the Xbee 802.15.4 product. They still use the USB dongle and module at the PC side to receive the data with both in transparent peer to peer mode (Default)? This should work just fine that way.
answered Oct 12, 2015 by mvut Veteran of the Digi Community (11,242 points)
The xbee dongle is connected to the USB port of th RPi(/dev/ttyUSB0) the UHF UARTRFID reader only uses TTL port on the (dev/ttyAMA0).
The question is how to i transmit RF signal from the rfid reader on the serial port of the Xbee which is on the USB port. Then the xbee transmits it to the xbee laptop(coordinator- basestation)
why are you not doing this the simple way.  Simply use a TTL to 3V CMOS level converter chip and 3V supply. Then you can connect the TTL level RFID reader direct to the XBee modules UART via the level shifter.  No Code to work with on a Raspberry Pi.  Simple Data out from the RFID reader = data in on the XBee.
UpdatedI connected the xbee like you said. Now I set the xbee coordinator to API/2 MODE and xbee  to AT model. When I recieve a message from the coodinator side it shows me only  this sign  ~
That is because you are in API mode.  Try using the Show Hex function in XCTU's Terminal tab and you should have more data.
ok got it Thanks!
The RFID reader is now connected to the xbee 2(AT mode-Router).
However, when the UART RFID reader is powered on by running a python script on the Raspberry PI(which the remote xbee2 is connected to), it automatically starts sending data packets to Xbee1(API-Coordinator).

Note: The python script(executed from the on the RPI) powers on the UHF RFID reader antenna then it starts detecting for passive tags.

Problem:
When the antenna is powered on it immediately starts sending data packets continuously to the PC (xbee 1 API).This is the decoded data recieved by the PC (XBEE1 API mode):
['0000', 'rx', 63, 'C\x03\x01', '00']. The only number that flunctuates is the rssi number

When a tag is then placed in front of the RFID reader it reads the tags and displays the tag number on the RPI.However,there is no visible change in data xbee2(AT MODE) transmits to the xbee1(API mode). XBee 1 still receives ['0000', 'rx', 63, 'C\x03\x01', '00'] The only number that flunctuates is the rssi number.

Question:

I want to transmit the tags epc tag numbers read from the RFID to the computer(xbee1 API) so that I use the epc tag numbers read to trigger an event on the computer(Xbee 1)?

How do I go about it. Thank you!
This is where I would take the radios out of the picture and just connect it to a PC to see if the RAW data changes or not. This allows you to then connect it direct to the RPI and see what happens and to have something to compare it with. Once you have that working, then and only then should you add the radios.
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