I try to measure and digitize an analog signal and send it to my pc so I can read it with the terminal of XCTU.
For that purpose I got two XBee Series 2 (XB24-Z7CIT-004). The receiving module is connected via a CP2102 USB to UART bridge to the computer.
The sending module is voltage supplied (3.3 V) and the analog signal (max. 600 mV) is connected to PIN 20 (AD0). Also a reference voltage of 1.2 V is present at PIN 14.
Using the Test/Query-option XCTU says both modules are XB24-B so I put firmware 1220 (ZIGBEE ROUTER/END DEVICE AT) on the receiving module and firmware 1020 (ZIGBEE COORDINATOR AT) on the other, broadcasting one. I programmed both modules with the same PAN-ID and each others addresses and the broadcasting module got its DIO0 programmed as an ADC.
As you may can imagine now: it’s not working…
Everthing else seems to work. When I perform a range-test I get 100% back and I was even able (in API configuration) to remotely read and write the other module, but the ADC does nothing!
So, how do I set up the XBees-ADC so that it’s working? In which way do I have to program the modules for that?
Could it be that I wrecked the ADC because at the beginning I always put 3.3 V on the VREF-Pin (yeah, I know…stupid me)?
Thanks in advance for helping!
I still don’t know what to do…I know this seems to be a stupid question but I can’t get this fixed.
I don’t know what more to do than programming PIN 20 (AD0) as ADC. The datasheet doesn’t reveal so much concerning this…
Is there some more stuff I have to do in order to start the conversions and read the results in the XCTU-Terminal? Is it possible to damage the ADC by putting 3.3 V on the VREF-PIN?
Here’s how I wired the whole stuff:
Receiving-Xbee:
PIN1 (VCC) <— 3,3 V
PIN2 (DOUT) —> CP2102-RXD
PIN3 (DIN) <— CP2102-TXD
PIN10 (GND) <— GND
Broadcasting-XBee:
PIN1 (VCC) <— 3,3 V
PIN10 (GND) <— GND
PIN14 (VREF) <– 1,2 V
PIN20 (AD0) <— analog signal with the same GND as the XBee
Really, I’m thankfull for any information you can give!
Ok, case closed. Looks like I fell into the firmware trap. Used Zigbee instead of ZNet2.5 firmware. It’s working perfectly now!
Just wanted to let the people know who are also beginners like me and might have the same problems.
leave the vref open or connect with ground using 100nf capacitor.
you can use any of the file there in \dia_da\src\devices\xbee\xbee_devices*.py
for example you can use xbee_sensor.py
Actually, there are two methods to get the value from XBEE channels
you go to \dia_da\demos\green_getting_started\green_getting_started.yml and change the setting first
then open telnet and run python dia.py after that open telnet again now with port number 4146 and channel_dump as showing in following video http://www.youtube.com/watch?v=RTRTcYL67ys
method is bit complex but I prefer that
if you want to know that please reply…
Hey Kishwar!
Thanks for your answer. But sorry…as I told one post before you everything works fine now. The problem was that I used the wrong firmware. I tried so many firmwares before but now I have the correct one…what a stupid mistake. Sorry for bothering you because of that and thanks again!