dixiedregs Posted February 4, 2015 Share Posted February 4, 2015 Hi, It's a long shot but does anyone out there have a schematic for the Martin RS485 interface? It's the old unit from the 90s with DMX512 in and out and a seperate Martin protocol output. I have a faulty one that I'd like to fix if possible, the DMX in is OK but no Martin output. Have checked most stuff with scope but just can't get any further without a schematic. Even Martin don't have one! Link to comment Share on other sites More sharing options...
timsabre Posted February 4, 2015 Share Posted February 4, 2015 Don't have a schematic but it wasn't very complicated - can you post a photo of the board (both sides) and it can probably be worked out from that?The Martin output was just another RS485 chip, have you tried swapping that? Link to comment Share on other sites More sharing options...
dixiedregs Posted February 5, 2015 Author Share Posted February 5, 2015 Don't have a schematic but it wasn't very complicated - can you post a photo of the board (both sides) and it can probably be worked out from that?The Martin output was just another RS485 chip, have you tried swapping that?Hi, Yes will do that tomorrow. What I have managed to figure so far is that the 485 chip is OK (replaced) and then scoped and there's no input. Working across the output side I now suspect the microcontroller or maybe EPROM. I cannot figure how the output side is driven by the input side. I would usually look for optos, but none! Started off at a blown transorb on the output side so I think that the unit has seen a "power event"! Thanks, Paul Link to comment Share on other sites More sharing options...
Recommended Posts
Archived
This topic is now archived and is closed to further replies.