How to Test a RS485 Connection

www.blackbox.com/Catalog/Category.aspx?cid=381,1908,1909

Try these or similar--G'luck

This http://www.blackbox.com/Catalog/Detail.aspx?cid=151,156,181&mid=1770 will test RS-232 connections using LEDs. You will need a pair of RS-232 to RS-485 converters to make this work. Or you can try this http://www.microstep-mis.com/index.php?lang=en&site=src/products/others/ct232_communicationtester and connect it to an RS-232 connector on a PC. You will need to wire the RS-485 connections based on the equipment you are using. There is no "standard" RS-485 jack.

lockitup, While I was working in the US I came across a company called Smart Cables (or something like that). They had quite an array of equipment that might suit your needs. I purchased some items from them and I used them to both test and configure RS232/ RS485 connections (it was like a break out box with alot of dip switches and leds etc). I am trying to find some more details for you but I cannot locate it at the moment, if I do then I will post them here - you may already know of this company. Perhaps someone else can point you in their direction.

Regards

Mr. WA Snow

Yes, it is called a logic analyzer

If it is a physical problem then one answer could be to connect the RX and TX together in a loop at the terminator end and using an RS485-232 adaptor plug into a laptop serial port on the front end, run Hyperterminal (there are better terminal programs but this is the generic supplied with Windows). Using a reasonably high bit rate, say 115200bps, check to see if any characters entered on the keyboard are echoed correctly. This however, will not necessaily prove the integrity of the wiring beyond doubt, but its a good starting block. It may be a good idea to remove one of the cameras (I'm assuming that they are a specific manufacturer with a designated protocol) and connect it directly to the RS485 connecter of the controller via a short peice of TP cable, if it will not control the camera then I would assume the RS485 driver has been zapped, and depeneding on your SMT rework abilities it may need a return to the manufacturer for repair.