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XBEE RF module

PostPosted: Wed Nov 25, 2009 3:42 pm
by windfrentor
Hi,
I am interested with this RF module and i am not really understand after read through the data sheet provided.

1. Since the operating voltage of this device is 2.8 – 3.4 V, is it possible i use voltage divider rule to reduce the voltage from 5v to 3.3v by using two resistor?

2. may i know this device sent and receive data in character(ASCII)?[like the moxbotix EZ-1 i'm using now?]

3. I plan to use this device for indoor purpose with obstacle like wall. Is it still can operate?

4. Anything that i should consider other than the supply voltage since i planning to use the serial transmistion to sent and receive data using micro-controller(PIC).
Thanks.

Re: XBEE RF module

PostPosted: Wed Nov 25, 2009 3:55 pm
by ober
windfrentor WROTE:
1. Since the operating voltage of this device is 2.8 – 3.4 V, is it possible i use voltage divider rule to reduce the voltage from 5v to 3.3v by using two resistor?

2. may i know this device sent and receive data in character(ASCII)?[like the moxbotix EZ-1 i'm using now?]

3. I plan to use this device for indoor purpose with obstacle like wall. Is it still can operate?

4. Anything that i should consider other than the supply voltage since i planning to use the serial transmistion to sent and receive data using micro-controller(PIC).
Thanks.


1. No, you cannot use this method because the XBee module will have internal resistance too when it is operating and will further affect your voltage divider.

2. Try to search ASCII from google, it mean when it send 1, the data received is 49 in decimal. A is 65 decimal.

3. It will affect the communication range, but still it can operate. Estimated 30 meter for XBee, 100 meters for XBee Pro. Still this is only estimation.

4. Power supply, interface logic for Tx, Rx are in 3.3V. The pins are also not standard. You have refer to our blog for the pin : http://blog.cytron.com.my/?p=1374

Re: XBEE RF module

PostPosted: Wed Nov 25, 2009 9:08 pm
by windfrentor
Hi,thanks for your reply. If i buy the "XBee Pro Starter Kit ",what i need to do is to connect the device to the micro-controller directly.correct me if i'm wrong. Besides,the XBee Pro Starter Kit send and receive data in ASCII format just like the maxbotix EZ-1 ultrasonic sensor?May i know this device need an inverter like the ez-1?Thanks

Re: XBEE RF module

PostPosted: Thu Nov 26, 2009 12:37 pm
by sich
1. Since the operating voltage of this device is 2.8 – 3.4 V, is it possible i use voltage divider rule to reduce the voltage from 5v to 3.3v by using two resistor?

You need a 3.3V voltage regulator. Please note that the TX and RX voltage level are also 3.3V. You cannot connect it directly to uC operating at 5V.

2. may i know this device sent and receive data in character(ASCII)?[like the moxbotix EZ-1 i'm using now?

Maxstream provides software to configure the XBee module. AT commands are used for this purpose.
Anyway, i think you're asking about the communication protocol between two XBee or among a few XBee. Since you are the one who decide what to transmit, you'll receive what you've transmitted. If you'd transmitted ASCII codes, you need to handle the data you received as ASCII codes.

3. I plan to use this device for indoor purpose with obstacle like wall. Is it still can operate?

Like Ober said. My experience is when the area has other 2.4GHz RF operating, like WIFI, the max range and data accuracy will be affected.


We definitely recommend you to use SKXBee starter-kit because you only need to take care of UART communication in that case. Connect SKXBee TX to uC RX and vice versa, then 5V and Gnd. So simple! ;)

Re: XBEE RF module

PostPosted: Thu Nov 26, 2009 1:36 pm
by windfrentor
HI sich,

1.That's mean for example i sent a charactor 'R' to the other XBEE, I will receive charactor 'R' also.Right? I just want to confirm.
2.May i know what are the configurations that i can set using the software provided by the MAXSTREAM?
3.If i buy the starter kit,that's mean i can just connect the XBEE to controller and start to communicate and no need to set anything? Thanks

Re: XBEE RF module

PostPosted: Thu Nov 26, 2009 10:33 pm
by sich
1. Yes, you are right.

2. The software provided is X-CTU. You can configure the module network address, destination address, interface data rate, and so on. Please refer to the datasheet for more info: http://www.cytron.com.my/datasheet/WirelessDevice/manual_xb_oemrfmodules_802.15.4.pdf

3. Anyhow, you still need to set some of the parameters mentioned above.

Re: XBEE RF module

PostPosted: Thu Jul 15, 2010 6:37 pm
by fitrialif
can i use external antenna for xbee....what is the effect if use small antenna with big antenna...would it increase the range....tq

Re: XBEE RF module

PostPosted: Fri Jul 16, 2010 3:10 pm
by sich
If not mistaken there is one model with the connector for u to put on ur own antenna. But there should be specifications of the antenna that needs to be followed. I believe simply changing the default antenna will only reduce the performance of XBee. However, XBee has several models with different antenna design for different performance.