solarix Posted February 15, 2006 Report Share Posted February 15, 2006 I have succeeeded in building the core and 2 DOUT modules from scratch on proto boards. I have the capability of using MIDI "music" to controll 110 VAC light, sequencing by playing the keyboard into Cakewalk.In testing I have been able to get the DOUT modules to run on a maximum of 45 foot of cat5 wire. For my application (Christmas Lights), 45' would be OK however, I would like a total cable length of 100', some of this length is between DOUT modules some between Core and the first DOUT module.Is some way of extending this distance with an active line driver or some other design?Thanks! Quote Link to comment Share on other sites More sharing options...
raphael Posted February 16, 2006 Report Share Posted February 16, 2006 Extending the cable length between core and DOUT and in between the DOUTs is no good idea! There are high frequency signals on these cables and with loger cables data transmission will become unstable. So please only extend the outputs themselfes. Quote Link to comment Share on other sites More sharing options...
Wise Posted February 16, 2006 Report Share Posted February 16, 2006 I'm sure that with a differential line driver like a RS422 driver you could get way longer than 100' without corrupting data. Just my first thougts. Check out this chip: http://focus.ti.com/lit/ds/symlink/sn65lbc179.pdfUp to 10Mbps, how fast is the DOUT,DIN chians scanned ?3 pairs of these should work. Plus gnd and +5v.Could be an idea to a new "extend module" ;D wouldnt work with AINs, just for DIN and DOUT..../Wise Quote Link to comment Share on other sites More sharing options...
TK. Posted February 16, 2006 Report Share Posted February 16, 2006 Up to 10Mbps, how fast is the DOUT,DIN chians scanned ?ca. 2 MbpsBest Regards, Thorsten. Quote Link to comment Share on other sites More sharing options...
Wise Posted February 16, 2006 Report Share Posted February 16, 2006 ca. 2 MbpsSweet, then it sounds doable.I'll sleep on this one :)/Wise Quote Link to comment Share on other sites More sharing options...
solarix Posted February 17, 2006 Author Report Share Posted February 17, 2006 Wise,I am pleased to see a possibility. 100 meg ethernet works without issue for 300 ft. I am sure there is a way to have 2 meg 100% perfect over 100 ft. Looking at the DOUT data lines with a scope, it doesn't appear to be a whole lot different than RS232, just faster and using less robust master hardware (the 452). My DOUT module failures on long runs are most related to the 5+ volt line and voltage drop on long runs due to the current draw required by powering 32 opto-isolators for the triac boards, so I have changed to a ditributed power arrangment placing a7805 and filter caps on each DOUT card and running +12 on the power line, this has improved stabilityt. I will look into the line drivers, probably buy a few and build to see what it ends up running like.Thanks again!Jerry Quote Link to comment Share on other sites More sharing options...
Wise Posted February 17, 2006 Report Share Posted February 17, 2006 probably buy a few and build to see what it ends up running like.Just order some samples från Texas ;DWith this line driver you could use a separate PSU at the DOUT/triac boards, just be sure to connect the GND of that psu and gnd of the core together. And be sure you use TP-cable for the data lines.Found some interesting documents, it's for rs485, bat it's similar tp 422:http://www.embeddedsys.com/subpages/resources/images/documents/microsys_art_RS485.pdfhttp://www.national.com/an/AN/AN-847.pdfKeep us informed about your progress/Wise Quote Link to comment Share on other sites More sharing options...
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