IMU Brick 2.0 + RS485 Master Extension

[Siddhant]

Hi,

I was wondering how the 2 components work together exactly. Can i directly mount the RS485 master extension on the IMU Brick using the stack connector and then use the RS485 to get the output signals? Or do i need another Master brick in between? Requirement is to send the IMU Gyroscope signals/values over a distance of more than 10 meters atleast and could go upto 20 meters.

Any help is appreciated.

IMU Brick: https://www.tinkerforge.com/en/doc/Hardware/Bricks/IMU_V2_Brick.html

RS485 Master Extension: https://www.tinkerforge.com/en/doc/Hardware/Master_Extensions/RS485_Extension.html#rs485-extension

Thanks,

Siddhant

[rtrbt]

Hi,

The RS485 Extension only works with a Master Brick (that's why it's called Master Extension ;) ). So at least two Master Bricks, two RS485 Extensions and one IMU Brick are required. The Master Bricks have to be bottom most in the stack, for example

RS485<---------->RS485
IMU              Master<-->PC
Master

should work.

[Siddhant]

Hi, thanks that helps a lot! :) Once the communication is configured this should enable transmission over longer distances using RS485 cables, right? 

[Siddhant]

Also I am looking to integrate a total of 6 IMU stacks in the project that will send gyroscope data to a PC from 6 different arms. I will use Labview to read this data. Does this mean i will need 6 Sets of IMU Stacks and Receiver Stacks:

IMU Stack 1..6         Receiver Stack 1..6
RS485<---------------->RS485
IMU                    Master<---------------------->PC
Master

Or can I do it like this (Using multiple IMU Stacks (IMU+Master+RS485) on the input side connected to one Receiver RS485 Extension for each and one Master for all the receiving RS485 stacks):

IMU Stack 1             Receiver Stack 1
RS485       <---------->RS485(1)
IMU                     
Master

IMU Stack 2 <---------->RS485(2)
IMU Stack 3 <---------->RS485(3)
IMU Stack 4 <---------->RS485(4)
IMU Stack 5 <---------->RS485(5)
IMU Stack 6 <---------->RS485(6)
                        Master<--------------------->PC

If i can do this, any tips on how to configure each receiver RS485 using the Receiver Master?

[rtrbt]

Hi,

One receiver stack should be enough. You can assign a unique slave address to each of the IMU stacks via Brick Viewer, as per this guide.

For the configuration, connect the IMU stacks via USB, configure them and then build the RS485 bus, the configuration is saved persistently on the extensions. This also means that you can plug the RS485 extensions on the receiver stack (one after another; a stack with two RS485 extensions will not work) and configure them there.

[Siddhant]

1 hour ago, rtrbt said:

This also means that you can plug the RS485 extensions on the receiver stack (one after another; a stack with two RS485 extensions will not work) and configure them there.

Sorry I didnt get this :( Could you please explain it maybe with an illustration as you did before? Thanks!

[rtrbt]

1 hour ago, Siddhant said:

Sorry I didnt get this :( Could you please explain it maybe with an illustration as you did before? Thanks!

I just meant, that you need to configure each RS485 Extension only once, as the configuration is saved in the extension's memory. For this you don't have to build the bus already, but can instead just plug in a stack like this:

RS485
Master<--USB-->PC

Then configure the RS485 Extension, unplug the stack, swap the extension and so on.

[Siddhant]

So you mean after configuring the RS485 extensions indicidually using a Master Brick, i can later stack all the configured RS485 bricks on top of 1 Master brick? Should that work? Like in the following example i mentioned above?

IMU Stack 1                        Single Receiver Stack 
(Master + IMU + RS485) <---------->RS485(1)
IMU Stack 2            
(Master + IMU + RS485) <---------->RS485(2)
IMU Stack 3
(Master + IMU + RS485) <---------->RS485(3)
IMU Stack 4
(Master + IMU + RS485) <---------->RS485(4)
IMU Stack 5            
(Master + IMU + RS485) <---------->RS485(5)
IMU Stack 6            
(Master + IMU + RS485) <---------->RS485(6)
                                   Master<------------USB------------>PC

bearbeitet September 24, 2020 at 14:50 von Siddhant

[rtrbt]

No you can't stack more than one RS485-Extension on a stack. However you can build a bus roughly like this:

IMU Stack 1                        Single Receiver Stack 
(Master + IMU + RS485) <---------->RS485(1)
IMU Stack 2                  |     Master<---USB---->PC
(Master + IMU + RS485) <------
IMU Stack 3                  |
(Master + IMU + RS485) <------
IMU Stack 4                  |
(Master + IMU + RS485) <------
IMU Stack 5                  |
(Master + IMU + RS485) <------
IMU Stack 6                  |
(Master + IMU + RS485) <------

This is documented here: https://www.tinkerforge.com/en/doc/Hardware/Master_Extensions/RS485_Extension.html#rs485-bus-assembly