Author Topic: what I would like to see ....  (Read 12178 times)

oric_dan

  • Jr. Member
  • **
  • Posts: 64
what I would like to see ....
« on: January 06, 2016, 10:47:47 PM »
[maybe this is available and I haven't seen it]

.... is an easy way to connect a lowpowerlabs RFMxx radio to a regular Arduino board such as an UNO, namely, something like a nice "plug-in shield" so you could forego having to stick a bunch of jumper wires into the usual Arudino female headers (and which I find to be a much less than optimal arrangement), or having to solder up a prototyping board.

Ideally, what I would like to see is a Moteino, or better yet Moteino-Mega, laid out with standard UNO form-factor female headers, and with decent 1-Amp voltage regulators, and the RFM radio wired on-board.

Then I could plug in an ethernet shield and connect to my router, and also an LCD shield on top of that. Then I would have a nice self-contained unit with no trailing wires that I could use as the Hub of a local RF network, and so I could easily connect the network to the internet. So, one unit altogether:

Hub Board (UNO form-factor):
--> RFMxx radio (on-board) --> other Moteinos
--> Ethernet shield (plug-in) --> router
--> LCD shield (plug-in) ~ menuing

Yes, no, maybe?
« Last Edit: January 06, 2016, 11:02:25 PM by oric_dan »

Felix

  • Administrator
  • Hero Member
  • *****
  • Posts: 6464
  • Country: us
    • LowPowerLab
Re: what I would like to see ....
« Reply #1 on: January 06, 2016, 11:09:19 PM »
Nice idea. What about a Moteino-UNO with no MCU but that can take a Moteino or MoteinoMEGA (headers for both). Then you could swap between MCUs by plugging different Moteinos if you wanted I guess... and for MEGA the extra headers would be on a side.
That would require a bit more soldering to get headers into the shield and into your Moteino, and would require 2 items (the shield itself and the Moteino). But it would be cheaper than with MCU onboard. A possible issue would be if the Moteino in the middle of the board is sticking too high up and could touch any stacked board on top.

The problem with atmega1284 ($8.4) is it's an expensive chip compared to atmega328 ($3.58), more than double. To factor that into a product you have to multiply it by a factor that will allow for some margin if you don't want to work for free. If you do that, you gather the wrath of the ESP8266 and chinese ArduinoMini fans who think everything in the world should cost no more than $3. So how do you make a product (product means business, ie profit) that is cheap and flexible and easy to use/make/test/distribute?

Anyway it's something I will consider, but my current focus is on another few things. But let's keep the iron hot and juggle some ideas of what features the ideal Moteino-UNO-board would be.

oric_dan

  • Jr. Member
  • **
  • Posts: 64
Re: what I would like to see ....
« Reply #2 on: January 07, 2016, 12:00:31 AM »
Felix, you're 1000% correct - anymore, it's a problem to try and compete with the Shenzhen boys, given costs of production [and shipping] in america. I like your idea of having layout for both 328 and 1284 DIP chips, and then someone could plug in whichever chip they like, although the dual routing might be a pitn with a 2-layer pcb.

OTOH, if you were to leave off the FTDI chip and use an adapter instead, as you do at present, I should think you could do "individual" 328 and 1284 pcbs with UNO form-factor for about the same cost as your current Moteino and -Mega boards. The only real difference would be the cost of a bit more real estate. I've always liked the UNO form-factor, as it's small and you can use all the standard Arduino shields. It just needs better v.regs than the std Arduino boards use. Plus it would be really nice to have everything self-contained for use as a central network Hub that could connect directly to a router.

I designed my own 328 and 1284 pcbs a couple of years ago, and which I use for all of my projects. I use 3-row headers, since most of my projects are robots. The board below, built in 2013, shows an RN-XV plugged in, but anymore I've gone away from the 2.4G band. I had initially thought about selling these things, but then Shenzhen exploded.

Height of the 1284 DIP chip sticking up is not a problem, in regards inference with plugin shields. It's the same as on a regular UNO board with DIP28, but you'd not have any problem if you used your current SMT chips.

Just some thoughts.

EDIT: oh yeah, you would need to make sure the RFM radio were located somewheres so the antenna wouldn't conflict with plugin shields, but then I would definitely put a reverse-SMA connector on the pcb. BTW, the DIP8 socket allows me to plug in an SPI eeprom or 128KB RAM chip.
« Last Edit: January 07, 2016, 12:11:54 AM by oric_dan »

Felix

  • Administrator
  • Hero Member
  • *****
  • Posts: 6464
  • Country: us
    • LowPowerLab
Re: what I would like to see ....
« Reply #3 on: January 07, 2016, 08:12:00 AM »
Good ideas, nice pcb you got there!
The more I think about it the more I am inclined to lean towards putting everything on the board, including MCU. I would go with an atmega1284 for added memory and more GPIO. THose who want to prototype would benefit from a middle way to a real Arduino MEGA, more expensive but net superior to a UNO.
One thing I can't quite settle or see the whole picture is the voltage, I feel I am missing something. I could run the whole thing at 5V then interface 3.3v to the radio and FLASH. Then people that are having issues with 3.3v could just use this board. That would break away from the Moteino 3.3v tradition though, but it could run the MCU at 20mhz, if I source yet another part just for that.

Funny thing is I designed and made some Moteino and MEGA that run at 5V, same format as the 3.3v boards, but never mass produced them. They just used resistor networs to divide voltages and talk to the radios/flash, they worked just fine.

jra

  • Jr. Member
  • **
  • Posts: 81
  • Country: us
Re: what I would like to see ....
« Reply #4 on: January 07, 2016, 12:20:06 PM »
@oric_dan Take a look at the http://www.firebirduino.com/sb_bb_v3/.  Says it is a standard Arduino UNO R3 form factor, accepts a 328 or a 1284 and has a connector for a nRF24L01+.  Charles Hallard has designed breakout boards for a variety of RFMxx radios that use the nRF24L01 connector, see https://oshpark.com/profiles/hallard so maybe this combination would work for you.

oric_dan

  • Jr. Member
  • **
  • Posts: 64
Re: what I would like to see ....
« Reply #5 on: January 07, 2016, 02:04:24 PM »
jra, thanks for the links. My original suggestion is something like the Sleeping Beauty, but with RFM radio layout.

Felix, a few more ideas ...
I definitely prefer the 1284, and use the board shown for most of my projects anymore. You'll notice my board does have everything on it, so it'll make a complete robot: 5/3.3V 1A v.regs, radio, extra RAM/eeprom chip, piezo, 32KHz xtal layout, Arduino female headers plus 3-row male headers, and I2C header. Sensors and servos plug right in. The 328 chips don't have enough RAM or IO pins for a decent robot.

One thing I did compromise on was to put the ICSP header is the "wrong" place, since the XBee socket and 5V regulator took up so much space. However, only the Ethernet shields use that header to my knowledge, so I have some that are hardwired to D11..D13, and I rewired others so they'd plug in. If the board had both DPAK vregs and a smaller layout for RFM radio, then the 1284 chip could be moved back, and the ICSP put in the usual place. But no issue anyways with SMT 1284 chips. And you could add a header on the right side for the extra 1284 I/O pins, as you mentioned.

Anymore I use DPAK v.regs for both 5V and 3.3V regulators on my newer boards. They are small, very cheap, and have superior heat characteristics to SOT-223/23.
http://www.digikey.com/product-detail/en/LD1117DT50TR/497-1238-6-ND/1848396

There is a jumper on the board that can switch the cpu Vcc between 5V and 3.3V. If you look "closely" at the oscillator frequency vs Vcc curves in the AVR datasheets, you'll see that at 3.3V the allowable freq shown is actually about 13.3 MHz, so using a 16 MHz xtal is only overclocking by 20%. I've never had any problem with a 16 MHz xtal and 3.3V, and many other people on the Arduino forum have done likewise. I do have voltage-dividers under the XBee radio socket for when Vcc=5V, but anymore I mostly use Vcc=3.3V anyways.

One other thing, there is plenty of room to have more than a single SOIC8 layout for SPI flash/RAM, and I would have at least 2 such layouts. Also, my boards have series-Rs for protection in all I/O lines, but they take up a lot of space. I would however include 1K series-Rs at least in the Rx,Tx lines going to the FTDI connector, so then the FTDI adapter pin voltages wouldn't be a problem.

 EDIT: I would also put a jumper on the Vin pin on the FTDI header, so it wouldn't conflict with direct power to the board.
« Last Edit: January 07, 2016, 02:29:25 PM by oric_dan »

Felix

  • Administrator
  • Hero Member
  • *****
  • Posts: 6464
  • Country: us
    • LowPowerLab
Re: what I would like to see ....
« Reply #6 on: January 07, 2016, 04:57:29 PM »
oric_dan,
It really sounds like you already got everything in your board, except the radio?
If that's the case, all you'd need is a breakout for the radio with appropriate voltage buffering. Would that work?

oric_dan

  • Jr. Member
  • **
  • Posts: 64
Re: what I would like to see ....
« Reply #7 on: January 07, 2016, 07:49:30 PM »
Yeah, I've already done that a couple of times with my Tredici-1284 board, stuck a radio on a small fiberboard using double-sided tape, and placed in the XBee area and hardwired to the SPI pins. My 2 network Hubs mentioned in the other thread do this. It helps that I have 3.3V 1A regulators on all my boards.
https://lowpowerlab.com/forum/index.php/topic,1494.0.html

However, my original intent of this thread was that I thought the Moteino world could make use of an official board coming from your shop that could be used as the "central Hub" for the rest of a Moteino network, and able to mount ethernet, LCD, and other regular shields. I would design it more like a regular UNO board, but with the 1284 chip, rather than including all the special things I have on my board. Nice 1A DPAK v.regs, an SMT cpu chip, and layouts for radio, 2/ea SOIC8s, and an extra header on the right side. It would cost little more than your Moteino-Mega to produce.

Felix

  • Administrator
  • Hero Member
  • *****
  • Posts: 6464
  • Country: us
    • LowPowerLab
Re: what I would like to see ....
« Reply #8 on: January 07, 2016, 09:42:02 PM »
It would cost little more than your Moteino-Mega to produce.
I feel it could cost quite a bit more :)
Regarding the DPAK, that will be good for lots of power but there will be the crowd that will complain that it's not low power enough. We could just slap a response like it's not meant for low power but I feel like I almost agree it should be low power friendly too. What do you think about that?

oric_dan

  • Jr. Member
  • **
  • Posts: 64
Re: what I would like to see ....
« Reply #9 on: January 07, 2016, 10:56:30 PM »
You would know better of course, but I figure the parts would be about the same as on the current Moteino-Mega, except for the additional $0.26 DPAK 5V regulator, plus 6 sqin area rather than 2 sqin. I don't know how much cost the expanded real estate would add. The Arduino female headers would jack up the cost, but pretty much everyone has those on their own anymore, and you could probably have a stripped-down option sold with no headers included, so 3X real estate would be the main added cost.

My feeling about power is that, this board would be intended as the "Hub" for a Moteino network and be located in a central location and likely be connected to the PC much of the time, so power draw would not be a big issue. You still have your low-power Moteino and -Mega boards to use for all the remote nodes. So, this board would mainly be to tie everything together as a central core, and for connection to the router, etc. Ethernet will always draw a lot of power.

My home automation system actually has 2 Hubs like this using my Tredici-1284 boards, one Hub for the in-condo RFM12 security / environmental monitoring network, and the other Hub using the RFM69 radios to connect to my robots and the SUV outside on the other side of the bldg in the carport. The RFM12s don't have enough power to make it to the SUV reliably, but work fine for inside the condo.

I use a separate Arduino Mega2560 board as a common Base Station connecting to the 2 Hubs via RS232, and have the Ethernet board and LCD on it. This seemed like a natural way to go, since I have 2 networks using 2 different radios. But for only 1 network, the Hub could have RFM radio, ethernet shield and LCD, although it would take a bit of extra coding to support all 3 via SPI.

Hmmm, it just occurred to me that the "new" Hub board could also be designed to plug in an ESP8266 wifi module for connection to the router, rather than via Ethernet. There should be plenty of room for that. So, that's high-power once again. I am equivocal about the ESP8266 modules, however, as my experience of a year ago is that they are somewhat unreliable, but maybe their firmware is better now. But it's another possibility.

WhiteHare

  • Hero Member
  • *****
  • Posts: 1300
  • Country: us
Re: what I would like to see ....
« Reply #10 on: January 08, 2016, 12:17:48 AM »
@oric_dan:  Are you saying its primary purpose is to connect your PC to the Moteino(s) using ethernet/wifi?  i.e. creating a virtual serial connection?  If so, there's an easier way of doing that via wifi-only using just an ESP8266.  If you feel you also need the wired ethernet connection, then maybe Felix's Pi gateway, or perhaps even just a plain Pi that runs a bash file with a few linux commands on boot-up, would be an option you'd want to entertain.  Probably the $9 C.H.I.P. could do it as well.
« Last Edit: January 08, 2016, 01:19:51 AM by WhiteHare »

oric_dan

  • Jr. Member
  • **
  • Posts: 64
Re: what I would like to see ....
« Reply #11 on: January 08, 2016, 02:03:21 AM »
WH, there are several possibilities. Using the RPi is one, but then that requires that one buy the Pi, and also learn to use it. My initial thought was that using an Arduino board for the Hub would be cheaper and directly inline with using the Moteino and -Mega in the first place.

The other business was just several possible connection schemes for the Hub.
- its primary use is the central point for the Moteino network.
- then, you could choose how you want to connect it to the rest of the world.
- either directly via FTDI to the PC,
- or via Ethernet shield to your router [which is how my Base Station is connected],
- or via wifi [ESP8266] to the router.
The UNO form-factor would allow any of these.

Also, my Base Station also has an LCD shield with a menuing system, so I can access it manually without having to turn on my PC at all. So, it's all standalone, and the PC needn't be turned on when I'm out of town for instance. The Base Station gets to the outside by sending Tweets and data to Xively. For that matter, the Base Station/Ethernet/Router pathway also serves webpages locally, which I can access using my Android Tablet. All of the latter software is available in Arduino-land. So I do it every which way,

WhiteHare

  • Hero Member
  • *****
  • Posts: 1300
  • Country: us
Re: what I would like to see ....
« Reply #12 on: January 08, 2016, 10:53:03 AM »
I've just never seen atmega's do very well at serving web pages.  Not enough oomph.  The web pages they can serve tend to be rudimentary, and with slow turnaround.  If you're determined to go that route, maybe consider using a Due or similar?

oric_dan

  • Jr. Member
  • **
  • Posts: 64
Re: what I would like to see ....
« Reply #13 on: January 08, 2016, 01:32:48 PM »
WH, you're entirely correct, thanks for pointing that out. Arduinos are not the best webpage-servers in the universe, and no doubt totally miserable for hosting dynamic pages.

I am just using simple HTML pages that allow basic monitoring and simple control of the home automation system. A sample page is shown below. I can monitor things, and turn switches on and off as shown. My overall system is half-implemented at present, but the idea is it will be standalone [ie, absent the PC] and will use the Android tablet for basic remote control inside the house.

Currently, my "more powerful" processor boards use 96-MHz Teensy3.1 modules, and the picture shows the HTML software being tested on this, but it was initially developed on the Arduino. I'm pretty sure a mega1284 Hub with RFM radio and Ethernet card could handle the RF network and also serve pages such as this. For a really fancy home automation system using the RPi, there is this guy who frequents the Arduino forum.
http://www.desert-home.com/2013/09/raspberry-pi-home-automation-process.html

EDIT: another thing is, I currently have no plans to allow direct access "into" the home automation system via the web from outside, so the web stuff is minimal. It does send "out" Tweets and data to Xively, so I can monitor the condo while traveling. So, my original idea for an UNO form-factor Moteino board wasn't something on too grand a scale overall.
« Last Edit: January 08, 2016, 01:43:38 PM by oric_dan »

joelucid

  • Hero Member
  • *****
  • Posts: 867
Re: what I would like to see ....
« Reply #14 on: January 09, 2016, 04:41:02 AM »
Quote
Arduinos are not the best webpage-servers in the universe, and no doubt totally miserable for hosting dynamic pages.

On the other hand at least with 433Mhz the Pi just causes too much interference. Costs me easily an impact of -15 in RSSI at times. I like the idea of a very light-weight gateway that only transcodes between radio and IP. Then do the heavy lifting either on a Pi or in the cloud.

Imagine smth like code bender, only you don't hook anything up to your laptop. Installs happen via wireless updates and you also develop your backend directly in the tool. All that's necessary at home is a battery of Moteino's and a tiny IP GW, possibly just a Moteino with attached ESP8266.

Joe