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Troy

Enabling the scanner run bit

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Hi, I am having a few problems with deviceNet (never used it before). Now a little bit on what I am doing and what equip I am using. Im am building a motor overload training aid for electrical apprentices, it for my final year project for my electronic engineering degree. I am using : 1769-L32E controller 1769 6 i/p 4 o/p digital I/O 1769 4 i/p 2 o/p Analogue I/O 1769-sdn E3 (5-25A) DSA 4/2 (100-DNY42R) Software: RSlgx5000 v13 RSlinx 2.5 RSNetworx for devicenet 3.21 Qn1 I have got the scanner (address 03) and E3 (address 05) working and they can be seen and manipulated via devicenet software, I went to try and enable bit 0 of the module command array to make scanner work but could not find where to do it. All stuff I have read just tells me about the array but not actually how to access it and enable/disanble bits inside it. Qn2. I was able to bummble my way through connecting the E3 and scanner fairly successfully, though upon trying to connect the DSA is where I have hit a problem. For the life of me I cant get it to work. I have set the node address = 04 on the adjustable switches on the outside. I thought it was how I have connected the cable (I have just daisy chained from scanner to E3 to DSA). If someone can help me out that would be great. P.S The inforamation I have got of this site is unreal, one of the best sites I have ever seen for technical inforamtion and help.

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Assuming the SDN is in slot 6 1. Local:6:O.CommandRegister.Run 2. Did you verify your baud rate? Do you have your terminator resistors on both ends on the Devicenet trunk? What lights you got on the DNY module, any? Give me a definition of what you mean by daisy chain? Everyones is different. CAN+ from on module should be hooked to CAN+ of the next module,etc

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I have attached a file of my devicenet cabling connections. I can get three different scenarios on the DSA. When I trun power on and both are connected 1. Both DSA and E3 flash green. or I have the E3 connected and all is running fine, I then add the DSA and it make the E3 flash red on Network and Trip led. when I try and connect just the DSA I get nothing. It is confusing Cabling.doc

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You should have a terminator or each end of your Devicenet network.. Can you see the DSAs in RsNetworks (RsLinx if you don't have RsNetworks)?

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I got the scanner to run (Thanks). No I cant see the DSA in RsNetworks or RSlinx. I got the scanner and e3 up and running fine and then when I connected the DSA it dropped the network, the E3 had red flashing leds on network and trip. Is there a fault with DSA.

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1. Have you got the trunk terminated with 121 (120) ohm resistors at each end as TW suggests. 2. Sounds silly but have you checked the connections to the DSA ?

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1. I have got the trunk terminated with 120 ohm 1/4w resistors. 2. I have swapped cables from the E3 to the DSA to make sure it wasn't the cable. I have tried to just connect the dsa and scanner with no luck.

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Good for you, by the way, for taking on what can be a complicated network for a first-time user. Be patient and don't get all superstitious and start forgetting the basics, like too many of my customers do. I think that you either have invalid MAC ID settings, a Baud Rate mismatch, or a defective DSA. Because you described the E3 as having dial switches for the DeviceNet address, I can deduce that it's a "version 5" unit. Those little rotary switches can be very delicate, so get an appropriately sized screwdriver to move them, and use a light touch. The rotary switches have a slot, with dots on one side like this -: the number on the dot-bracketed side of the switch is the number the switch is designating. You described the behavior of the two devices as follows: 1. When I turn power on and both are connected, both DSA and E3 flash green. 2. When I have the E3 connected and all is running fine, I then add the DSA and it make the E3 flash red on Network and Trip LEDs. 3. When I try and connect just the DSA I get nothing. DeviceNet runs at three possible baud rates: 125 kb/s, 250 kb/s, and 500 kb/s. The 1769-SDN comes out of the box set for 125 kb/s by default. Most A-B devices, including the E3 and the DSA, implement an "autobaud detection" function. Both the E3 and the DSA do allow you to disable the autobaud function, so it's a remote possibility that the DSA has the autobaud function disabled. Ordinarily a device will power up and "listen" to the network for traffic, to see what data rate the network is running at. The network LED will generally blink green/red/off during this listening phase. Once the device has figured out the data rate, it will broadcast a "DUP MAC ID CHECK" packet. If it gets back a reply, it knows that there is a device already using the node number it intended to use, and it will politely refuse to join the network and turn on a blinking red network LED. If a device has Autobaud disabled and is set for a different baud rate than the rest of the network, then when it is plugged in it will skip the "listen" portion and just go ahead and send the DUP MAC ID CHECK packet. If it's at the wrong data rate, this can cause other devices on the network to see bad packets (because the bit durations are wrong) and declare a "BUS OFF" state. Watch the 1769-SDN as it boots up. It will flash some numbers across the display. My demo, for example, does this: 88 (LED checkout) 02 (00=125 kb/s, 01=250 kb/2, 02= 500 kb/s) 80 (idle mode) 00 (the SDN's node number) You could try re-configuring the 1769-SDN for all three data rates (use RSNetworx or the Node Configuration Utility) and cycling power to the DeviceNet with just the SDN and the DSA connected. The DSA should come up with a flashing green network LED during one of those iterations, and you'll be able to go online with it via RSNetworx to figure out if it has Autobaud disabled.

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I mis-spoke; the utility to change the 1769-SDN's data rate or node number is the "Node Commissioning" tool, accessed either separately or from the Tools -> Node Configuration menu in RSNetworx. (also, try to get an updated RSNetworx version; I'm running 6.00) I tried setting the scanner to 500 kb/s and disabling Autobaud on the DSA, leaving it at 125 kb/s. The scanner came up with Error 79 (unable to transmit on network) and the DSA came up with a solid red Mod/Net LED. Note: I think I was wrong about the 1769-SDN's bootup sequence. That "2" must be the firmware major revision, because it stays a "2" no matter what data rate I set the scanner for. The other scanners I work with (1747-SDN and 1756-DNB) show the data rate, then the major/minor firmware revisions. Since you don't get a solid red LED when the DSA is connected, I'm starting to discount the baud rate mismatch hypothesis, and lean toward a damaged DSA. One last thing (can you tell I do a lot of DeviceNets ?). Power up only the DSA on the network (no scanner.) The Mod/Net LED should blink green then red, then go off and stay off. If this doesn't happen, then you probably have a bad DSA, probably one with a defective CAN transceiver chip. I can't explain why it would flash green in concert with the E3 when powered up simultaneously, if it does not perform as described above when it is alone.

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Ken, Thanks for that after some frustrating times I got it to sort of work. When RSnetworx was browsing the network it found the scanner then the E3 anf finally the DSA, The network light on the DSA went solid green then I got an error in Rsnetworx. DNET:0008 The device at address 04 is not registered on this computer. Then the DSA had a green flashing network led. Now I had this problem when I first started, I'll explain it to you. When I first started my project I had demo ver of RSLgx 5000 V15(Downloaded From AB), demo RSnetworx for DeviceNet v3.21 (Downloaded From AB), rslinx I thnk 2.31 (Downloaded From AB). I could practice ladder logic and look at the parameters and set up a devicenet network - all good. The company I am doing my university project for stuffed up ordering the software, they finally ordered it but it will take a few weeks. I spoke to the guys at excell control and they where great they lent me RSlog 5000 v13 and rslinx 2.5. I wiped all the demo software of my NB. installed the proper software and the demo rsnetworx, all installed fine. Opened deviceNet and tried to build network, I added the scanner and it came up with ? Unrecongised device. After 20hrs I figured out that it must have been an EDS problem, I installed RSLinx 2.31 on my PC then copied the EDS folder and put it into the EDS folder on my laptop and problem was fixed. Thanks for your comment on your first reply, even though I have had a few problems I love working on AB PLC's, used to microcontrollers/VHDL, its a good change. All these problems I am nutting out will only help. You only become a guru once you have encountered a lot of problems.

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