DSD TECH SH-U12 RS485 to TTL 5V Board with MAX13487 Chip for Raspberry Pi Arduino and Other MCU

Works great. I use it to control a vfd Via rs485.

I purchased a cheap RS485 to TTL and it could not auto switch fast enough. This one did it with ease. If I would have purchased this one first, I would have saved myself a day and a half of debugging. So I consider this on to be of much better quality.

So I did not see any reviews for this product but wanted to write something up. I needed to use a Raspberry Pi to connect to a BACnet network and I needed to read and write serial data. I really thought the Raspberry pi would work by itself but had issues with the connection I tapped into. I was reading at the wrong voltage and needed to step over. This device allowed me to connect on the serial tap and it works amazingly. Every script I wrote previously and have tried to debug to figure out why it was not working were now working. I may not be testing this to its limits but it was able to allow me to get the voltage to the appropriate level for me to read and write on the serial channel.

Might be OK for a point-to-point connection without line termination. Output is disabled (not active) whenever input is high.

This RS485 converter works as advertised. My application only required 9600 baud but operation was flawless with an Arduino Mega 2560. One thing I found was that, for my application, I needed to reverse the "A" and "B" RS485 signal lines. I don't know if this is an error on the board silk screen or my slave device label is in error. I am using the SH-U12 to talk to an ABB PID pump controller using Modbus protocol. If you can't get the converter to talk to your RS485 buss, try reversing the connection. This has worked so well, I am now using three of these!

These TTL to RS485 converters work very well. Nice diagram on the bottom of the unit to let you know what's what as far as terminals. The board is large for it's function, but at least it has mounting holes to keep it steady.

The LED TX/RX indicators are reversed which makes absolutely no logical sense at all. When transmitting, the RX indicator lights up. When receiving, the TX indicator lights up. It's just so dumb. TX on the SH-U12 goes to RX on whatever you are connecting it to. RX on the SH-U12 goes to TX on whatever you are connecting it to. Some people commenting here seem surprised by this arrangement but it is normal Serial communication setup. After all, a TV station transmits to "A RECEIVER" in your TV. Right?? A+ connects straight through to A+, B- connects straight through to B-, and GND connects straight through to GND between two SH-U12 units. The packaging is well done and thought out, but I can't find SH-U12 on their website and a little documentation would go a long way.

I was able to get the board to work. The model (version) i received is not longer documented on the manuf web site and no other information was available. Double check the version you are getting to ensure you can get documentation. I received SH-U12. Make sure you have the doc for this model available before you order. It worked, I just don't have any support or documents.

using them for all sorts of projects, i.e. communicating between 2x arduinos or 2x teensys. Great bit of kit.

Gutes Produkt, kommt in einer ordentlichen Verpackung. Funktionalität einwandfrei. Im Gegensatz zu MAX485 muss beim MAX13487 Chip die Übertragungsrichtung nicht händisch geschaltet werden was sehr bequem ist. Zu den negativen Punkten: es wäre wünschenswert den Durchmesser der Montagelöcher in der Produktbeschreibung mit anzugeben. Diese sind M2 (Grüße an denjenigen der diese Frage mit "kann ich nicht sagen" beantwortet hat: eine solche Antwort hilft _überhaupt_ nicht weiter). Und da wäre noch der Preis. Günstigere MAX13487-Alternativen funktionieren genauso gut (vielleicht nicht bei Randbedingungen wie dem versprochenen 15kV ESD-Schutz, dies müsste aber extra getestet werden). Also als Einzelbestellung an der Preisschmerzgrenze noch OK. Wenn man aber mehrere davon braucht, wird's schnell happig.

Marche parfait...

Great quality, DSD never let's you down. Don't bother with cheaper alternatives as they rarely work.

Contenta. Está funcionando a las mil maravillas