I use DCC-EX for my main layout. I got an Arduino Mega with WiFi built onboard as I felt the less hats the better, less points of failure. It was a little more steps to get the onboard WiFi working, but once done, it is just as easy to use as anything commercial, and a lot cheaper.
Cool. What I like the most about the modular concept is that there are many ways to achieve the same goals. Lots of learning opportunities and quite some fun (sometimes some frustration as well...).
That is the core functionality, but there is more. It gives reverse polarity protection when using the DC plug, the 5V rail is now providing up to 3 amps, which is helpful if you connect other devices, and you do no longer have to worry about the Arduino onboard LDO when feeding higher voltages to VIN (up to 18V is no problem, the absolute limit is around 24V). Then you can connect the IoTT Stick to it, which turns it into a wireless Loconet command station with WiThrottle server, Loconet over TCP access for JMRI and other software, and the Loconet over MQTT gateway. Furthermore, you then can connect a WS2812 LED chain to display the status of current sensors, turnout positions etc., completely transparent between DCC EX and Loconet. Plus some additional functionality of the IoTT Stick, like e.g. the event handler, which lets you define IFTTT (if this, then that) sequences to implement automated signals and more, similar like what you can do with EX RAIL, but no coding, just clicks on the web page of the IoTT Stick.
First I have to say your videos are fantastic. Really eye opening for someone new to the hobby like me. One question tho. This video uses the 2A arduino motor shield instead of the 5A IBT-2 powershield. Is this just because the motor shield comes pre configured in hardware and software? To use the powershield, you only need to solder the pins(or buy the a preconfigured board) and configure the software? For my simple newbie setup, I think I would get a Mega, 5A powershield, aux board, and IoTT stick. I only have 1 loco at the moment, so can expand later to add a programming track.
Thank you. Yes, you can use the PowerShield as replacement for the motorshield and only use a single channel. The only thing you need to make sure is to ground the unused analog input as if left open it may trigger the over current protection. See the installation note for configuration examples: myiott.org/index.php/iott-stick/function-hats/redhat-shield-for-dcc-ex/47-ibt-2-power-shield
Great video on the DCC_EX when I try to use the red hat in engine driver it keep me for a port number where do I find it other than that keep up the good work
If the WiThrottle Server is activated, you get a WiThrottle tab in the Red hat web page. Click it to view and set the port number. The default is 12090, which is the WiThrottle standard port on ED.
In the DCC-EX documentation discribing use of the ESP-01-S for wifi, it recommends using the 5v power supply and a 3.3v regulator to power the ESP-01. Can the AUX shield perform this function? Further, could the AUX shield provide a connection in place of pins 18 and 19 on the Mega?
The DCC AUX board does not have an onboard 3.3V regulator, but as recommended in the DCC-EX docu you can connect one to the 5V. The DCC AUX 5V provides a maximum of 3Amps compared to the 1Amp of the Arduino onboard 5V regulator, s that should not be a problem. You can get 5V from the soldering pads of the LED chain or from pins 1 and 8 of the Stick connector. The Serial port is only used if you are installing an IoTT Stick on the AUX shield. By default it is going to IOs 0 and 1. However, if you place the red jumpers on the other side, Tx and RX are routed to the two soldering pads at the edge of the board, from where you can make a connection to the serial pins you want to use, e.g. pins 18 and 19. If your board is 3.3V, you should also shorten the two soldering pads on the other side of the jumpers to shorten the voltage divider used for 5V boards.
No, it's no longer needed when using the DCC AUX shield which allows for a single source power supply of up to 18 Volts. See videos #115 and #116 for the technical background information, if interested.
I have not touched the actual product, so my comparison here is based on what is known about it so for, mainly schematics and data sheet of the H Bridge driver chips. The most obvious difference is that the 8874 shield has two H bridge drivers, so it is a replacement board for the motorshield and provides two output channels. And it has an onboard DC/DC converter, which provides a 7V output to the VIN pin to simplify wiring. When looking into the details, there are more subtle differences. The H Bridge driver 8874 is rated 6 Amps. so running it at 5 Amps. is relatively close to the max current. The BTS7960 on the other hand has a max current of 43 Amps, so there is more room. More important though is the combined ON resistance of both channels. For the 8874 this is 200mOhms, which leads to a power dissipation at 5 Amps of 5 Watts on a rather small chip. We will have to wait for reports from users, but I don't think it is possible to load it with 5 Amps continuous without the chip getting quite hot. The ON resistance of the BTS7960 on the power shield is 16mOhms, which leads to about 1 Watt at 5 Amps, and this is distributed on 2 chips. So, the PowerShield has some reserve and I am planning on testing it for officially rate it at 8 Amps,. which would be great for G scale. The other notable difference is the DC/DC converter. It outputs 7V and feeds it to the VIN pin, which means the 5V for the Arduino is still created by the LDO on the Arduino with a maximum current of 0.5 Amps or so. The PowerShield on the other hand uses a 5V DC/DC converter which goes directly to the 5V pin and has a rating of 3 Amps, so that it is no problem to supply additional boards with 5 V, and even operate a LED chain as demonstrated in the last video. I chose this concept because it maintains the modularity, so if you have other boards in the stack that need higher voltage than 7V, e.g. a motorshield, you can still go with a single power supply. If you wanted to use a motorshield in conjunction with the 8874 board and feed say 12V to it, you still would need a second DC supply, because the VIN pin is at 7V fixed. I am not sure about the flexibility of IO selection on the 8874 shield. I get the impression it is only possible to use a limited set of IO pins to drive the board. The PowerShield for sure offers full configurability and you can use all IO and Analog pins of the Arduino board, so you have maximum flexibility to configure according to your needs. That's just what I know so far, I'm sure more will become clear in the future.
Yes, it works as soon as you have a DC/DC convertor for the 5V supply. Older style RedHats have an onboard DC/DC converter (that green add-on PCB on the lower side). Or you use the DCC AUX board for the same purpose, which has an onboard DC/DC converter.
@@IoTT OK, so if I have an arduino motor shield, I only need one 12v power supply plugged into v1 redhat to power full stack. But I assume the IOTT Power shield would still require its own 12-15v supply for HO because of the 5A.
With the PowerShield you connect DC to the PowerShield input and as long as you are not using higher voltage than 18V DC, you can add a jumper on the PowerShield to supply it to VIN, so you can power the entire stack from a single power supply. If you need more than 18V for track, you would need a second source for the rest of the stack and leave the jumper on the PowerShield open.
Hi Hans, As always an excellent video, and a great job you do for this hobby : I wanted to know if you can help me with this question: Today I have the original configuration that was previously used for a DCC-EX station, which is installing the Arduino Motorshield on the Arduino Uno or Mega, but chopping the famous VIN Pin, which was necessary to remove to avoid burning the Mega / Uno. In this case, installing the stack as you show in this video, will I have a problem not having the VIN Pin on my Motorshield plate? PS: I have ordered my DCC AUX Shield, to start restructuring my components 👌 thank you.
Well, it depends. If you just cut the pin between motorshield and Arduino, it is sufficient to just put the DCC AUX shield on top of the stack and power the DCC AUX shield. The Arduino will get the 5V supply from DCC AUX and that is all that is needed. If you cut the trace on the Motorshield board, you have to resolder it as it is needed to power the shield (instead of using the terminal connector)
Thanks a lot. This video deserves a lot more views!
I use DCC-EX for my main layout. I got an Arduino Mega with WiFi built onboard as I felt the less hats the better, less points of failure. It was a little more steps to get the onboard WiFi working, but once done, it is just as easy to use as anything commercial, and a lot cheaper.
Cool. What I like the most about the modular concept is that there are many ways to achieve the same goals. Lots of learning opportunities and quite some fun (sometimes some frustration as well...).
So the Aux shield is simply a voltage buck converter that sends 12 or 14 or however many volts to the motor shield but only 5V to the Arduino?
That is the core functionality, but there is more. It gives reverse polarity protection when using the DC plug, the 5V rail is now providing up to 3 amps, which is helpful if you connect other devices, and you do no longer have to worry about the Arduino onboard LDO when feeding higher voltages to VIN (up to 18V is no problem, the absolute limit is around 24V). Then you can connect the IoTT Stick to it, which turns it into a wireless Loconet command station with WiThrottle server, Loconet over TCP access for JMRI and other software, and the Loconet over MQTT gateway. Furthermore, you then can connect a WS2812 LED chain to display the status of current sensors, turnout positions etc., completely transparent between DCC EX and Loconet. Plus some additional functionality of the IoTT Stick, like e.g. the event handler, which lets you define IFTTT (if this, then that) sequences to implement automated signals and more, similar like what you can do with EX RAIL, but no coding, just clicks on the web page of the IoTT Stick.
First I have to say your videos are fantastic. Really eye opening for someone new to the hobby like me. One question tho. This video uses the 2A arduino motor shield instead of the 5A IBT-2 powershield. Is this just because the motor shield comes pre configured in hardware and software? To use the powershield, you only need to solder the pins(or buy the a preconfigured board) and configure the software? For my simple newbie setup, I think I would get a Mega, 5A powershield, aux board, and IoTT stick. I only have 1 loco at the moment, so can expand later to add a programming track.
Thank you. Yes, you can use the PowerShield as replacement for the motorshield and only use a single channel. The only thing you need to make sure is to ground the unused analog input as if left open it may trigger the over current protection.
See the installation note for configuration examples: myiott.org/index.php/iott-stick/function-hats/redhat-shield-for-dcc-ex/47-ibt-2-power-shield
Great video on the DCC_EX when I try to use the red hat in engine driver it keep me for a port number where do I find it other than that keep up the good work
If the WiThrottle Server is activated, you get a WiThrottle tab in the Red hat web page. Click it to view and set the port number. The default is 12090, which is the WiThrottle standard port on ED.
In the DCC-EX documentation discribing use of the ESP-01-S for wifi, it recommends using the 5v power supply and a 3.3v regulator to power the ESP-01. Can the AUX shield perform this function? Further, could the AUX shield provide a connection in place of pins 18 and 19 on the Mega?
The DCC AUX board does not have an onboard 3.3V regulator, but as recommended in the DCC-EX docu you can connect one to the 5V. The DCC AUX 5V provides a maximum of 3Amps compared to the 1Amp of the Arduino onboard 5V regulator, s that should not be a problem. You can get 5V from the soldering pads of the LED chain or from pins 1 and 8 of the Stick connector.
The Serial port is only used if you are installing an IoTT Stick on the AUX shield. By default it is going to IOs 0 and 1. However, if you place the red jumpers on the other side, Tx and RX are routed to the two soldering pads at the edge of the board, from where you can make a connection to the serial pins you want to use, e.g. pins 18 and 19. If your board is 3.3V, you should also shorten the two soldering pads on the other side of the jumpers to shorten the voltage divider used for 5V boards.
Hi Hans . Is it not needed to cut the Vin connection on the Bottom of the Motor shield ?.. Sorry I see someone else has already asked the Question.
No, it's no longer needed when using the DCC AUX shield which allows for a single source power supply of up to 18 Volts. See videos #115 and #116 for the technical background information, if interested.
Hi Hans, wenn does the powershield will be available again? Regards from Aargau Tom
Hi Tom, the PowerShield is available, what's currently missing is the DCC AUX Shield. Will be back in about 10 days.
@@IoTT I meant the dcc aux shield. Will check back and order eveything in once. Thanks
so just announced DCC-EX Motor Shield EX-Motorshield8874. what's the difference compered to the iott 5amp shield?
I have not touched the actual product, so my comparison here is based on what is known about it so for, mainly schematics and data sheet of the H Bridge driver chips.
The most obvious difference is that the 8874 shield has two H bridge drivers, so it is a replacement board for the motorshield and provides two output channels. And it has an onboard DC/DC converter, which provides a 7V output to the VIN pin to simplify wiring.
When looking into the details, there are more subtle differences. The H Bridge driver 8874 is rated 6 Amps. so running it at 5 Amps. is relatively close to the max current. The BTS7960 on the other hand has a max current of 43 Amps, so there is more room. More important though is the combined ON resistance of both channels. For the 8874 this is 200mOhms, which leads to a power dissipation at 5 Amps of 5 Watts on a rather small chip. We will have to wait for reports from users, but I don't think it is possible to load it with 5 Amps continuous without the chip getting quite hot. The ON resistance of the BTS7960 on the power shield is 16mOhms, which leads to about 1 Watt at 5 Amps, and this is distributed on 2 chips. So, the PowerShield has some reserve and I am planning on testing it for officially rate it at 8 Amps,. which would be great for G scale.
The other notable difference is the DC/DC converter. It outputs 7V and feeds it to the VIN pin, which means the 5V for the Arduino is still created by the LDO on the Arduino with a maximum current of 0.5 Amps or so. The PowerShield on the other hand uses a 5V DC/DC converter which goes directly to the 5V pin and has a rating of 3 Amps, so that it is no problem to supply additional boards with 5 V, and even operate a LED chain as demonstrated in the last video. I chose this concept because it maintains the modularity, so if you have other boards in the stack that need higher voltage than 7V, e.g. a motorshield, you can still go with a single power supply. If you wanted to use a motorshield in conjunction with the 8874 board and feed say 12V to it, you still would need a second DC supply, because the VIN pin is at 7V fixed.
I am not sure about the flexibility of IO selection on the 8874 shield. I get the impression it is only possible to use a limited set of IO pins to drive the board. The PowerShield for sure offers full configurability and you can use all IO and Analog pins of the Arduino board, so you have maximum flexibility to configure according to your needs.
That's just what I know so far, I'm sure more will become clear in the future.
I love that there is only one power connection. Does that still apply if you have Mega+PowerShield+Redhat now?
Yes, it works as soon as you have a DC/DC convertor for the 5V supply. Older style RedHats have an onboard DC/DC converter (that green add-on PCB on the lower side). Or you use the DCC AUX board for the same purpose, which has an onboard DC/DC converter.
@@IoTT OK, so if I have an arduino motor shield, I only need one 12v power supply plugged into v1 redhat to power full stack. But I assume the IOTT Power shield would still require its own 12-15v supply for HO because of the 5A.
With the PowerShield you connect DC to the PowerShield input and as long as you are not using higher voltage than 18V DC, you can add a jumper on the PowerShield to supply it to VIN, so you can power the entire stack from a single power supply. If you need more than 18V for track, you would need a second source for the rest of the stack and leave the jumper on the PowerShield open.
Hi Hans, As always an excellent video, and a great job you do for this hobby :
I wanted to know if you can help me with this question:
Today I have the original configuration that was previously used for a DCC-EX station, which is installing the Arduino Motorshield on the Arduino Uno or Mega, but chopping the famous VIN Pin, which was necessary to remove to avoid burning the Mega / Uno.
In this case, installing the stack as you show in this video, will I have a problem not having the VIN Pin on my Motorshield plate?
PS: I have ordered my DCC AUX Shield, to start restructuring my components 👌
thank you.
Well, it depends. If you just cut the pin between motorshield and Arduino, it is sufficient to just put the DCC AUX shield on top of the stack and power the DCC AUX shield. The Arduino will get the 5V supply from DCC AUX and that is all that is needed. If you cut the trace on the Motorshield board, you have to resolder it as it is needed to power the shield (instead of using the terminal connector)
Thank Hans,, I didn't just cut only pin, the track never cut it. @@IoTT