Micrologix 1500 network via MDS radio

T

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touchdown

The setup = ONE Micrologix 1500 connected on Channel 1 to an MDS licensed freq radio. Baud = 9600 8N1 , DF1 Full Duplex, FULL DUPLEX MODEM, node # 2 (CALL it the master). OTHER END = ONE Micrologix 1500 connected on Channel 1 to an MDS licensed freq radio. Baud = 9600 8N1 , node # 4 (CALL it the slave)

Problem => Radio attempts to transmit, but it is keyed constantly. I need to know what settings I need to place on the 1500 LRP in the comms on channel 1 to get it set for CTS and RTS.

Please help
 
On the Micrologix 1000's, the comm port was not capable of using the rts cts lines. It only used Rx, TX and GND. so when you used a modem with those, you had to make a cable that had RTS/CTS jumped out, or tell the modem to ignore those lines. But I'm not sure that is your problem. I just used a 1500 not too long ago, but i was using ethernet radios. The comm ports are supposed to be fully functional, just like the SLC com ports. So, here's the advice.
First, realize that MDS radios are continuously keyed, so if you are noting with a service monitor that the radio keep transmitting, thats OK. But, if the TX light is on steady, thats not right.
Second, check the radio, make sure its got the correct DCE/DTE setting.
third Make sure the radio is not in test mode with the reciever keyed. but, if this is the problem, it should automatically go out of test mode after a time.
Fourth, make sure the cable does not have any more wires connected than needed. Some of those pins on the MDS are marked as *Do not connect* and i think they mean it.
Fifth, i just remembered that i had a similar problem with a SLC once. I think resetting the processor fixed the probelm temporarily. but eventually, IIRC, i discovered that i had my MSG blocks all screwed up. I had them all firing off at once and as fast as they could go, and someone with AB told me that the comm buffers were probably getting full.

hope this helps. Post back when you find the solution.

-jeff
 
You could start with verifying radio comm, are both radios set up the same and are they the same series radios (A or B)? MDS has software to check communications, Datawatcher and RSIM. To use them you need the diagnostics enabled, that can usually be done with a plea for mercy to MDS tech support.
A master radio with the key light on all the time is allright if you are in "constant keyed mode". Is that desireable? Jeff was right in his comment about the cable, but in one experience I had I didn't need any connections other than RX,TX & Gnd, no jumpers. Verify with AB for the jumper.
If this is a new setup you can tweak alot of the settings in the radio to get good comm, you may not even need RTS & CTS, then you start on your 1500...let me know how it goes.
 
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