HOWTO - Make a BrewPi Fermentation Controller For Cheap

[day_trippr]

Hah! I parked this in an earlier reply while this thread was in limo.

I stumbled over these spiffy looking mini-XLR plugs and didn't want to lose the link while we wait for this thread to come back to life.

I've been using the all-plastic-body models (not the plastic and rubber ones which do indeed totally suck) which work fine but had I seen these a few months ago I'd have used them instead as the price isn't much higher...

Cheers!

 

[wbarber69]

Those work pretty good. But I've had trouble with all the mini-xlr's I've gotten that are Chinese made corroding.

 

[day_trippr]

Well that would suck, given where these things can end up in service.
I guess I'll stick with the plastic ones.

I wonder if a coating of BoeShield T-9 would be worth the effort?

Cheers!

 

[wbarber69]

I used the ones you linked to. I just injected a bunch of silicon into the housing to add a little protection.

 

[Borisfa]

I installed Debian on my olf netbook and now I waiting the hardwares I bought. So, lookink into Brewpi, I would like to ask how should (recommended) be the initial parameters for PID algorithm.

My system is for a conical fermenter and 45 L of beer.

Thanks,

Fabiano da Mata

 

[atoughram]

I added an encoder/switch to mine over the weekend. Its wired just like the schematic, an EC12 encoder with 10K pullup resistors and 0.1uf bypass caps. I've got it wired to the arduino as follows - Channel A = Pin 9, Channel B = Pin 9, and the switch is on pin 7, but it doesn't work.

Is there something that needs to be turned on in the Brewpi software to make it work?

 

[BrewCityBaller]

I added an encoder/switch to mine over the weekend. Its wired just like the schematic, an EC12 encoder with 10K pullup resistors and 0.1uf bypass caps. I've got it wired to the arduino as follows - Channel A = Pin 9, Channel B = Pin 9, and the switch is on pin 7, but it doesn't work.

Is there something that needs to be turned on in the Brewpi software to make it work?

I am guessing it is a typo, but you have Pin 9 listed twice.

Channel A should be on 8 and Channel B should be on 9. Switch on 7.

 

[atoughram]

I am guessing it is a typo, but you have Pin 9 listed twice.

Channel A should be on 8 and Channel B should be on 9. Switch on 7.

You're correct - Typo - sorry

 

[FuzzeWuzze]

I installed Debian on my olf netbook and now I waiting the hardwares I bought. So, lookink into Brewpi, I would like to ask how should (recommended) be the initial parameters for PID algorithm.

My system is for a conical fermenter and 45 L of beer.

Thanks,

Fabiano da Mata

Stick with the defaults, they should work just fine if your using a thermowell.

There are some minor things you may be able to do, but it wont change things significantly. But see how well it works with the defaults for a brew or two before fiddling with the PID settings

 

[day_trippr]

I could have sworn someone posted in this thread about running BrewPi using an Uno with an ethernet shield to communicate with the RPi side instead of USB. But the closest post I've found so far is from someone who was asking about going that route, not someone who had solved it.

Is this a false memory or does anyone else remember seeing something about this?

Cheers!

 

[thekraken]

I could have sworn someone posted in this thread about running BrewPi using an Uno with an ethernet shield to communicate with the RPi side instead of USB. But the closest post I've found so far is from someone who was asking about going that route, not someone who had solved it.

Is this a false memory or does anyone else remember seeing something about this?

Cheers!

I didn't see that, but I'm using rxtx pins and gpio instead of usb for serial comms. I don't know what your trying to do but that's an alternative to usb in case it helps.

 

[day_trippr]

I didn't see that, but I'm using rxtx pins and gpio instead of usb for serial comms. I don't know what your trying to do but that's an alternative to usb in case it helps.

You know, that might be a fall-back, thanks!

A wireless topology would be easier to implement given what I was thinking of doing. There's an aisle between my BrewPints box and my two brew fridges that would have to be crossed somehow. I'd like to bring those two fridges under the BrewPints umbrella without resorting to outright heroics.

I assume you had to rebuild the AVR code to make that work?

Cheers!

 

[thekraken]

You know, that might be a fall-back, thanks!

A wireless topology would be easier to implement given what I was thinking of doing. There's an aisle between my BrewPints box and my two brew fridges that would have to be crossed somehow. I'd like to bring those two fridges under the BrewPints umbrella without resorting to outright heroics.

I assume you had to rebuild the AVR code to make that work?

Cheers!

I didn't need to rebuild the AVR, the rpi picks it up on /dev/ttyAMA0, you just have to make one change to a brewpi config file, and make a change to a rpi system file or two. Sounds like your running multiple arduino's on one pi, I believe we're limited to just one arduino through the gpio pins unless theres some tricks I'm not aware of.

 

[day_trippr]

Interesting - so if I get that right, you're using the Arduino hardware serial port to talk to the RPi hardware serial port. It makes sense then that you didn't have to rebuild the AVR code in that case, though it raises a curiosity about those AVR signals also being connected to the (idle) serial/USB bridge chip.

There'd be a conflict with that in my case as the hardware serial port on the RPi is being used by an AlaMode shield for RaspberryPints support - its AVR uses AMA0.

But I believe the RPi has a provision for a secondary serial port, which presumably would be AMA1. I know the BrewPi host files that have to change on the "host" side to point to various transports, having gotten BrewPi mostly running on the AlaMode once, and having multiple Unos running via USB. I'd have to verify all that but if true that could be a viable alternative - that transport doesn't have to run fast, just reliably.

Still want to pursue a wireless solution. Worst case if I can port Elco's AVR code to a bigger core there'd be room to pull in the ethernet library to support the wireless shield without shedding BrewPi functionality...

Cheers!

 

[thekraken]

Hmm, the alamode is essentially what I made, I put a arduino pro mini on top of some protoboard that sits on the rpi gpio, a diy rpi shield.

There may be a way to breakout the gpio into multiple serials...

As for wireless I can't think of any solutions that don't involve custom avr code. I believe Elco is going to be releasing a new brewpi system soon that uses sparks as "wireless nodes" somehow. You may look into what he's up to.

 

[atoughram]

I've got one of these

http://www.ebay.com/itm/Wireless-Bl...062?pt=LH_DefaultDomain_0&hash=item43c62f6a86

that I was going to hook up to a megasquirt, but I bet it will work on an Arduino/rpi too - wireless serial.

Maybe in concert with a pro-mini?

 

[thekraken]

I've got one of these

http://www.ebay.com/itm/Wireless-Bl...062?pt=LH_DefaultDomain_0&hash=item43c62f6a86

that I was going to hook up to a megasquirt, but I bet it will work on an Arduino/rpi too - wireless serial.

Maybe in concert with a pro-mini?

I was just coming back to suggest Bluetooth. I've never messed with it my self, for the rpi end would an adapter show up as some port in /dev/ that you could use just like a serial port?

 

[day_trippr]

I'd have to investigate what the RPi has for a Bluetooth stack, but from my admittedly limited experience with Raspbian so far, I'd bet you can treat it like any other transport terminus, just need to know its logical name and plug it in.

The cherry on top of that solution is there are combo wifi/bluetooth dongles running on Raspbian. Don't know how reliable they've proven to be but it's a start...

Cheers!

 

[atoughram]

I was just coming back to suggest Bluetooth. I've never messed with it my self, for the rpi end would an adapter show up as some port in /dev/ that you could use just like a serial port?

I'd have to assume so, I know that module takes some initialization strings before it will work and thats why I didnt use it on the megaquirt at the time. but if you put a pro mini in between it and the arduino, you could program the pro-mini to initialize the BT and then pass the serial info from the arduino, I dont think the arduino will know the difference.

On the Rpi side, I wonder if a standard BT USB dongle would work?? And like you said, show up in /dev/tty*???

Could be...

 

[thekraken]

I'd have to assume so, I know that module takes some initialization strings before it will work and thats why I didnt use it on the megaquirt at the time. but if you put a pro mini in between it and the arduino, you could program the pro-mini to initialize the BT and then pass the serial info from the arduino, I dont think the arduino will know the difference.

On the Rpi side, I wonder if a standard BT USB dongle would work?? And like you said, show up in /dev/tty*???

Could be...

I see, use a pro mini as a relay, and since you can get them around $2-3 a pop on eBay (in bulk) that's not to costly either, no modifying the brewpi_avr necessary. Though, how much space would a Bluetooth module require in the brewpi avr itself? And how much room is left?

 

[atoughram]

I see, use a pro mini as a relay, and since you can get them around $2-3 a pop on eBay (in bulk) that's not to costly either, no modifying the brewpi_avr necessary. Though, how much space would a Bluetooth module require in the brewpi avr itself? And how much room is left?

Good question - the last .hex file I downloaded was 72,501 bytes.

The ATmega328 on my UNO has 32K of flash memory.

Obviously is cant all fit...

So your guess is as good as mine. From a programming stand point, programming the pro-mini as a relay is much easier than trying to decipher someone else's code and make modifications. The source code is on github https://github.com/BrewPi/brewpi-avr and Elco doesnt use the standard Arduino IDE, I believe he uses Atmel Studio.

 

[time2brew]

I added an encoder/switch to mine over the weekend. Its wired just like the schematic, an EC12 encoder with 10K pullup resistors and 0.1uf bypass caps. I've got it wired to the arduino as follows - Channel A = Pin 9, Channel B = Pin 9, and the switch is on pin 7, but it doesn't work.

Is there something that needs to be turned on in the Brewpi software to make it work?

It's difficult to make out the wiring from your photo but here's the encoder portion from the BrewPi RevC shield schematic.

Hope it helps

 

[thekraken]

I'd have to investigate what the RPi has for a Bluetooth stack, but from my admittedly limited experience with Raspbian so far, I'd bet you can treat it like any other transport terminus, just need to know its logical name and plug it in.

The cherry on top of that solution is there are combo wifi/bluetooth dongles running on Raspbian. Don't know how reliable they've proven to be but it's a start...

Cheers!

This looks promising!: https://www.adafruit.com/product/1588 for the arduino and https://www.adafruit.com/products/1327 for the rpi.

The ez-link description says "Linux is not supported at this time" but that doesn't make any sense to me as os compatibility is dependent on the bluetooth module on the rpi end. It looks like the ez-link is just plug and play.

[Edit] or this: https://www.adafruit.com/products/1628 Too bad neither of these are in stock right now.

[Edit] or this: https://www.sparkfun.com/products/12577 These things are expensive, I'm liking atoughram's suggested module.

 

[thekraken]

I'd have to assume so, I know that module takes some initialization strings before it will work and thats why I didnt use it on the megaquirt at the time. but if you put a pro mini in between it and the arduino, you could program the pro-mini to initialize the BT and then pass the serial info from the arduino, I dont think the arduino will know the difference.

On the Rpi side, I wonder if a standard BT USB dongle would work?? And like you said, show up in /dev/tty*???

Could be...

This article links to the same bluetooth module that you did. They seem to have it running "plug & play" on the arduino without initialization strings. Is that not the case?

 

[atoughram]

It's difficult to make out the wiring from your photo but here's the encoder portion from the BrewPi RevC shield schematic.

Hope it helps

Thanks, Thats exactly how I've got it wired.... I think...

I'll have to take a closer look at it and see where I screwed it up..

 

[atoughram]

This article links to the same bluetooth module that you did. They seem to have it running "plug & play" on the arduino without initialization strings. Is that not the case?

Might be - I didnt ever implement the BT module on my megasquirt, and never tried it on the arduino. I bet that there has to be some sort of initialization though, how else would you pair it to another device?

EDIT - After reading that article, they make it look easy dont they?? It's almost worth the three bucks for me to try that out. The BT module I bought doesnt have a fancy breakout board.

 

[atoughram]

It's difficult to make out the wiring from your photo but here's the encoder portion from the BrewPi RevC shield schematic.

Hope it helps

So... It's not how I had it wired... It's how I thought I had it wired...

Somehow I had transposed Pins 7,8, & 9 to pins 8,9, & 10.

Changed that around and presto! It works!

 

[day_trippr]

Gotta love a happy ending

Cheers!

 

[day_trippr]

The bluetooth solution looks promising, and it's cheap enough to go ahead and find out what the devilish details turn out to be. Found the Arduino board and a BT4.0 class 2 dongle that's worked on the RPi for $8 total, delivered by Monday by Amazon.

I'm in. We'll see where this particular worm hole leads...

Cheers!

 

[craigmw]

Sorry if I missed this in this HUGE thread....

Has anyone figured out a way to use the BrewPi temp logs to send an SMS message if the temp is too high or too low? In my case, I'm more interested in building a second BrewPi to monitor/control my 600 bottle wine cabinet, but I could see this function being useful for monitoring a ferm chamber in case something bad happens.