💬 Building a wired RS485 sensor network

[boozz]

@Reza
There are many options for detecting fake radio's. For me it works best to test them in a node that has a good working radio attached (preferrably far as far away from its parent node as possible) and exchange it with the suspected fake one.

There's also a thread in this forum that describes a method to test the quality of nrf24L01+ connections. It's a quality meter. I know for sure you can find this one using the search function.

By the way; about the wiring distance between a node and gateway: the fastest way to get an answer is to get multiple answers on such questions is using an universal search engine: www.google.com

[gohan]

@boozz
What are the codes on the NRF24 chip of the modules you consider being the best performing?

[hek]

@gohan

There is no easy way of telling by looking at it.

https://forum.mysensors.org/topic/1664/which-are-the-best-nrf24l01-modules

[Reza]

for wiring , is this true ?
rs485...............arduino
vcc......................5v
gnd....................gnd
DI.........................9
DE........................2
RE.......................10
R0........................8

[kimot]

@Reza

DI and DO depends on your board type.
Look at AltSoftSerial_Boards.h
DE and RE should be connected together and connected to pin,
which is defined in your program:
#define MY_RS485_DE_PIN 2

[kimot]

@Reza
http://cmss.pl/arduino/MySensor_RS485_test02_b.JPG

[Reza]

@kimot thank you friend :rose:

[Reza]

@kimot
for a raspberry pi gateway this wiring is true ?

[wimd]

@Reza No. You need to have your gateway inbetween. Your controller can't "talk" directly with you MySensors network. Wee the picture from kimot.

[gohan]

@wimd
actually RPI can act as gateway https://www.mysensors.org/build/raspberry , but I agree that's much easier to have an Arduino as a gateway

[Reza]

@wimd we can build a gateway with raspberrypi without arduino . @gohan saying true . but i have to use gpio for serial gateway because when i use a usb serial port after turn on/off or reboot raspberry can not detect my gateway... but with gpio i test and this is true, so i have to use gpio for gateway

[Reza]

if i use rs485 for my network , can solve problems about signaling and distance and wall? and solve problem about NACK ?

[kimot]

@Reza
Maybe your problem and its solution with "serial-through USB" connection on Raspberry is described here:

https://g0kao.wordpress.com/2013/08/08/usb-port-assignment-on-a-raspberry-pi/

[kimot]

@kimot
I am not sure, that Raspberry can work like RS485 gateway for MySensors RS485 network.
On a "quick" look through code, I do not find anything for RS485.

[gohan]

@Reza
Maybe it is worth a try and get a W5100 network shield and make an ethernet gateway. I have one now and so far I'm happy with it.

[Reza]

thank you friends

[Reza]

@kimot @gohan do you use a wired network with rs485 ? i have problem with rf24 and i want change my wireless network to a wiring network , but i want know with a rs485 all command are send? without error and NACK ? now for wireless network i have for example every 5 true commands 1 fail command(NACK)

[gohan]

@Reza
not yet, but I am getting the parts to make a wired rs485 network of 4 nodes + gateway. About the NACK error it should be handled by the library and retransmit the lost packet.

[pjr]

Currently there is no "hw" ack functionlity like the radio has.
You can check out the rs485 transmit code from here.

But you can of course use the ack functionality between controller software and node to make sure message will get to destination.

[Reza]

@gohan now my sensors lib how many send packet if first is lost ? how more this ?
i want after send command Turn on light Certainly