Open Source Mash Computer? - Page 2

mattreba · 01-08-2009, 07:27 PM

From a gas versus electric perspective... Who cares

The output channel could just as easily drive a gas solenoid valve and an igniter w/ flame detection. The computer doesn't really need to know what the heat source is.

First order of business: Platform selection.
The opto 22 platform looks way too expensive. We might get some ideas by studying their UI though.

I was planning around the Arduino because it looked cheap, easy and perhaps the most popular platform out there right now. I'd like to support a simple setup with two sensors and two output channels and possible have it configurable to support very complex configurations (assuming there is enough space for code). I think keeping it low cost but very usable would be the project directive. The Arduino might be slightly constrained for advanced setups but we could probably port the code to something like the Sanguino if need be down the road.

PicBasic looks like it requires a purchase of the compiler at around $200+. Arduino uses a free development environment. More info here: Arduino - HomePage

Any arguments for or against Arduino? Arguments for another platform?

mattreba · 01-08-2009, 08:03 PM

I'm thinking about what a super complex advanced setup might use to think about the upper reaches of what the platform might support. Personally, I think I'd stick with two temperature inputs and two outputs only because I'm cheap but...

Inputs:
HLT Temp (Analog LM34)
Mash Temp (Analog LM34)
HLT Volume (Magical volume measurement producing 0-5v calibrated to your volume or used as digital float switch for heat element cut-off)
Mash Volume (see HLT Vol)
Kettle Volume (see HLT Vol)
Kettle Temp (Analog LM34)
CFC Temp (Analog LM34)

Serial Output:
Serial Enabled 20 char x 4 line LCD

Digital Outputs:
Kettle Heat On/Off
Mash Heat On/Off
HLT Heat On/Off
Alarm
Pumps and valves

A single pump system would probably use the most valves. I can think of 12 possible valves (so 13 channels with the pump) if filling, sparging, boiling and cooling were all controlled (definitely not a first release objective):

Water In HLT
Water In Chill
Water in Mash
Water in Kettle
Pump In HLT
Pump In Mash
Pump In HEX
Pump In Kettle
Pump Out HEX
Pump Out Mash
Pump Out Kettle
Pump Out Chiller

Every multi-pump solution I came up with used fewer valves.

I think the Arduino could handle most setups though the max config here would probably require using an analog output linked to a second board providing an additional 10 outputs. The Sanguino could do it all with no additional board but would require soldering and costs a bit more. I'd like it if a non-developer could put together and program their system with little to no soldering.

**kladue** · 01-09-2009, 12:12 AM

What about the basic stamp board, looks like there are a number of interface boards available to interface analog sensors. One could start with a bare basic stamp system and expand as desired/needed.

mattreba · 01-09-2009, 02:40 AM

The Basic Stamp 2 is close but as you said analog inputs would require add-ons and the base product cost more than twice what the Arduino does. Is the main concern about programming in C? I don't think this version will be hard to pick up. There are tons of coding examples on Arduino's site.

I don't want to be a stick in the mud for Arduino but it seems hard to beat.

todbot blog » Blog Archive » Arduino, the Basic Stamp killer
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StoutFan · 01-09-2009, 02:46 AM

Could something be developed in VisualC and then transferred? I have a little experience with it and it's not to overwhelming.

Foosinho · 01-09-2009, 03:08 AM

Arduino programming is pretty easy. Plus, there is a pin-compatible upgrade for the current AVR chip used in the Arduino available now with twice the memory. I just started playing with one about 2 weeks ago, and I like the platform quite a bit. It's easy to develop for.

This is a project I'd definitely contribute to.

**kladue** · 01-09-2009, 03:56 AM

Just was looking at the 10 bit analog and wondering about the lack of resolution on the temperature sensors, and the inability to interface with thermocouples or RTD devices. Is low price the overall goal or is there a need for a low cost starter base unit with optional enhancements as budget and need grows. Another question is will the base unit execute a stand alone program or operate as an i/o unit with the control programming and gui's running on a more robust computer.

DharkMeadBrewer · 01-09-2009, 04:53 AM

Quote:

Originally Posted by kladue

Just was looking at the 10 bit analog and wondering about the lack of resolution on the temperature sensors...

10 bits should be more than sufficient resolution for mash control. 10 bit means there are 10 on/ off switches, this means that the board can provide 1024 bits of resolution, which is more than enough.

jcdillin · 01-09-2009, 12:58 PM

Quote:

Originally Posted by mattreba

From a gas versus electric perspective... Who cares

The output channel could just as easily drive a gas solenoid valve and an igniter w/ flame detection. The computer doesn't really need to know what the heat source is.

First order of business: Platform selection.
The opto 22 platform looks way too expensive. We might get some ideas by studying their UI though.

I was planning around the Arduino because it looked cheap, easy and perhaps the most popular platform out there right now. I'd like to support a simple setup with two sensors and two output channels and possible have it configurable to support very complex configurations (assuming there is enough space for code). I think keeping it low cost but very usable would be the project directive. The Arduino might be slightly constrained for advanced setups but we could probably port the code to something like the Sanguino if need be down the road.

PicBasic looks like it requires a purchase of the compiler at around $200+. Arduino uses a free development environment. More info here: Arduino - HomePage

Any arguments for or against Arduino? Arguments for another platform?

I think if it's going to be a chip with a daughterboard and not a standalone micro then it for sure should be Arduino

lustreking · 01-09-2009, 03:45 PM

I'm going to keep my eye on this. I'm pretty handy with a soldering iron, but haven't done any real coding in years.