tag:blogger.com,1999:blog-4922503085503427986.post6533799016588475961..comments2024-03-29T06:35:17.330-07:00Comments on Desert Home: More About XBee Broadcastdavehttp://www.blogger.com/profile/11608589214882334649noreply@blogger.comBlogger6125tag:blogger.com,1999:blog-4922503085503427986.post-70915194631807181192015-12-09T07:30:09.095-07:002015-12-09T07:30:09.095-07:00Depends on what you mean by simultaneous. The XBee...Depends on what you mean by simultaneous. The XBee can only send, or receive at any given time, but it can switch between the two really fast. If you need true duplex operation, you can't do it with only two XBees.davehttps://www.blogger.com/profile/11608589214882334649noreply@blogger.comtag:blogger.com,1999:blog-4922503085503427986.post-31690044098892114352015-12-09T03:03:01.360-07:002015-12-09T03:03:01.360-07:00Hi
just saw your blog and must confess it is wonde...Hi<br />just saw your blog and must confess it is wonderful. i want to ask how can i send and receive message simultaneously using two xbeesAnonymoushttps://www.blogger.com/profile/15800976793082838519noreply@blogger.comtag:blogger.com,1999:blog-4922503085503427986.post-55084887268305016252014-08-28T16:12:16.216-07:002014-08-28T16:12:16.216-07:00Bill, Yes, they certainly can. They aren't ca...Bill, Yes, they certainly can. They aren't called master and slave, their endpoints, routers and coordinator (only one of these). I have a network of about 12 of them that take care of various things around the house and report status back to a Raspberry Pi that does the work of coordinating the devices and logging stuff so I can look at it later.<br /><br />No, there's no one place where I talk about this specifically, but the entire site (well mostly) deals with how I started this stuff and developed it to where it is now ... mistakes and all. Take a look around and especially the tab up top about XBees. After a bit of reading, you'll start to get it. If you have questions, drop me a note. My email in in the "about me" cleverly disguised so the spambots don't target me.davehttps://www.blogger.com/profile/11608589214882334649noreply@blogger.comtag:blogger.com,1999:blog-4922503085503427986.post-47571656202902913712014-08-28T12:26:20.722-07:002014-08-28T12:26:20.722-07:00Dave,
I am new to blogging and may not be using p...Dave,<br /><br />I am new to blogging and may not be using proper etiquette, but let me say I admire your hardware and software expertise and the clear, excellent way you write.<br /><br />For a home network of 5 XBees, can one be designated the master and the others be designated slaves? Can data and commands be transmitted over the whole network? The message rate need not be high.<br /><br />If you have discussed this question or can refer me to something already available on the web, just say so and save your valuable time. A thousand thanks.Anonymoushttps://www.blogger.com/profile/16581844395671653022noreply@blogger.comtag:blogger.com,1999:blog-4922503085503427986.post-62629204119618114262013-09-18T21:29:42.826-07:002013-09-18T21:29:42.826-07:00Digi doesn't say specifically how big the rx a...Digi doesn't say specifically how big the rx and tx bufffers are; probably because they change from software release to release. There have been a number of folk that experimented with it and it appears the buffers are around 130 or so bytes in effective length. By effective I mean the XBee itself also puts things in there to send such as retries and forwards. That's why they enable the hardware controls so data input can be stopped if necessary.<br /><br />So, basically, the quicker you can get the stuff out, the less likely you are to fill up the rx buffer. The slower you stuff stuff in, you less likely you are to fill up the tx buffer.<br /><br />I have my sensors set up to transmit on a periodic basis and never seem to miss a packet from them. At least not anymore. When I was using them all in broadcast, the multiple retransmissions to get the data all around the network would flood it. Checksum errors abounded. I have a couple of long messages, by long I mean around 50 characters of payload. Those messages were torn to shreds by the various devices eating up airtime trying to forward them.<br /><br />In your case, there may be some tough problems to overcome. The XBee will listen to see if there is traffic on the RF, if there is, it will wait and try again. These delays are small, but may make the results invalid for two people hitting the button at almost exactly the same time. davehttps://www.blogger.com/profile/11608589214882334649noreply@blogger.comtag:blogger.com,1999:blog-4922503085503427986.post-31792518494148948942013-09-18T15:16:58.259-07:002013-09-18T15:16:58.259-07:00I have a question that I have not found an answer ...I have a question that I have not found an answer for and I'm guessing that you already have run the experiment that I am thinking about doing. Say you want to broadcast a remoteAtCommandRequest from 1 xBee say your coordinator, to get the battery voltage from all of your other xbee nodes. How do you handle all of the responses? Do you just try and parse all of the data to an Arduino and hope that you don't miss a packet? Or do you just have to give the command out to one node, handle the response, and then go on to the nest node? I honestly don't even know how big the Rx buffer on an xBee is (wondering if a bunch of packets could be stored on the xBee until the MCU can comb through all of the data). I'm building a jeopardy style game show buzzer system for a few of my friends that have a zainy trivia show. It's an interesting xBee application to have a many to one network where all of the nodes are controlled by people that can all send a packet at once and have to see which of them sent the packet first, a lot harder than having everything sent at nice timely intervals. And the system is running stably at 115200!<br />avid reader<br />DaveAnonymousnoreply@blogger.com