SparkFun Electronics Commentsurn:uuid:214d0e4e-f1b1-d287-ce26-ac5b4c9f82492024-03-29T00:11:53-06:00SparkFun ElectronicsAaronCarlton on BOB-09489 - USB to RS-485 ConverterAaronCarltonurn:uuid:0ffe2fa6-2a43-4ac6-2182-5db3ee1ad0572010-06-29T10:12:38-06:00<p>Doh, I mean JP5, Sorry.</p>
AaronCarlton on BOB-09489 - USB to RS-485 ConverterAaronCarltonurn:uuid:33770718-75ae-fe25-d580-9eaae700f2272010-06-29T10:11:34-06:00<p>You should not have to cut any pins, you should be able to use JP3, with the board as is.</p>
Garak on BOB-09489 - USB to RS-485 ConverterGarakurn:uuid:a3b9a508-4fbd-e1fe-73e8-cb4d4beb67b32010-06-22T10:20:54-06:00<p>If I wanted to use these for TTL serial do I need to cut the trace from the output of the SP3485 to the FT232RL?</p>
GlennE on BOB-09489 - USB to RS-485 ConverterGlennEurn:uuid:2af2dae9-bce7-8c8a-ad8d-2b37de2a7c192010-06-06T13:20:25-06:00<p>Cannot get this module to work with my existing 485 adaptors.<br>
I can recieve with this module but cannot transmit from this module. I noticed the RTS line did not come on. Also, tried setting windows terminal program to use hardware flow control but made problem worse.<br>
Please Help</p>
Nate on BOB-09489 - USB to RS-485 ConverterNateurn:uuid:6f1ecd7a-38f8-2d7f-ef66-a2a78196b39b2010-04-15T15:49:21-06:00<p>Excellent idea. I've added a 4-pin header that breaks out these extra pins.</p>
Nate on BOB-09489 - USB to RS-485 ConverterNateurn:uuid:45ea7682-291a-7d35-be01-84243e8589c12010-04-15T15:48:55-06:00<p>Thanks Jeremy! I've updated the design to connect TXDEN to DE and kept RTS connected to the LED.</p>
Nate on BOB-09489 - USB to RS-485 ConverterNateurn:uuid:ad1ce3c4-7d5a-8939-95e4-bdc679cff3e52010-04-15T15:47:32-06:00<p>Eeek! I'm sorry I didn't see this sooner. We'll get this board updated as quickly as possible.</p>
JeremyCole on BOB-09489 - USB to RS-485 ConverterJeremyColeurn:uuid:fc86abfa-57c2-f23c-1482-bf95805ead902010-02-22T05:02:55-07:00<p>This is a working hack to bypass RTS and use TXDEN from the FT232RL pin 13: <a href="http://www.facebook.com/photo.php?pid=11437053&l=7c89ad454b&id=503885429" rel="nofollow">http://www.facebook.com/photo.php?pid=11437053&l=7c89ad454b&id=503885429</a><br>
I even fixed the LED. This thing is fairly useless without the hack -- getting RTS working for this purpose is nearly impossible. SFE: Any idea why this wasn't set up like this in the first place?</p>
smee on BOB-09489 - USB to RS-485 Convertersmeeurn:uuid:4e10f8f0-c0d9-624e-0431-6aad1697b11b2009-12-03T06:29:00-07:00<p>It might be nice to have room for a header that connects to the unused pins of the RJ45. In the past, I've run RS485, power, and 1-wire through the same cat5 cable with good results. A header connecting to those pins on this board would make that easier.</p>
Ocean Controls on BOB-09489 - USB to RS-485 ConverterOcean Controlsurn:uuid:b0ea0fff-09b3-a94d-be15-7ae0a2c0ef572009-12-02T20:24:08-07:00<p>Also, the board is labelled with the "correct" A=Inverting (D-) and B=Non Inverting (D+) signal lines, but it is quite commonly used the other way around, (like in the data sheet for the SP3485), so it can be confusing as to which wire needs to be connected where.</p>
Ocean Controls on BOB-09489 - USB to RS-485 ConverterOcean Controlsurn:uuid:2012d061-f049-edf4-b89f-8959190f1b5e2009-12-02T19:28:54-07:00<p>This uses the RTS line to drive the Transmit enable, which means the controlling application must set the RTS line for long enough before sending out the data and turn it off straight after the last character, otherwise the first couple of characters might get scrambled in transmit and receive.<br>
It would be more sensible to use the TXDEN function (defaults to pin 13) in the FT232RL, which is designed to drive a 485 transceiver and will be set long enough before any data goes out the Transmit line, without the need for flow control on the controlling application.<br>
Maybe in Version 2?</p>