KegBB

Well, I've got all my parts together, and think I'm ready to go.

Mike - Have you had any luck in getting the schematic & PIC code ready? I've been bashing my head against the wall all morning trying to figure it out, so even if your work isn't complete, I'd appreciate any help you can give!

Thanks, Andy

Edited kegbot (May 3, 2005 13:35:30)

On 5/3/05, Andy Lintner kegbot@beowulfe.com wrote: > Well, I've got all my parts together, and think I'm ready to go. > > Mike - Have you had any luck in getting the schematic & PIC code ready? > I've been bashing my head against the wall all morning trying to figure > it out, so even if your work isn't complete, I'd appreciate any help you > can give!

Hi Andy,

Alright, I uploaded an image of the schematic from my CAD tool: http://wiki.kegbot.org/Image:Kegboard-v01-draft.png

It is, however, woefully incomplete -- but maybe it is enough to get you the basic idea. (I've not used this cad tool before, so my progress is probably a bit slower than it should be..)

As for the PIC code: no luck yet! Reason: can't find my PIC programmer. It is in a box somewhere, and my friend Andrew is bugging me to find it and flash him a PIC (see next paragraph).

I did, however, get some progress made a week or two ago. Andrew was in town from the east coast and demanded a kegboard, so we (mostly) built one on Saturday. It's different from my board in a few ways that make it simpler: - one relay instead of two (he didn't need fridge control) - no thermo sensor (same as above) - ftdi usb controller instead of max232

I should be able to get a parts list for both this 'junior' board and the 'original' board out there soon. Now that the draft image is out there, I'm sure it will bother me enough to correct it

mike

Edited mike (May 4, 2005 02:56:54)

Thanks Mike! That's enough to keep me busy for awhile hunting down components. My only questions is, what did you use for a temperature sensor to trigger the fridge relay? I'm thinking I'll end up using a DS1820 1-wire, but I'm just curious about what you went with.

Thanks, Andy

Edited kegbot (May 4, 2005 07:41:17)

On 5/4/05, Andy Lintner kegbot@beowulfe.com wrote: > Thanks Mike! That's enough to keep me busy for awhile hunting down > components. My only questions is, what did you use for a temperature > sensor to trigger the fridge relay? I'm thinking I'll end up using a > DS1820 1-wire, but I'm just curious about what you went with.

Yep, I use a DS1820. Microchip has a cheaper sensor, and you have some other options in this regard, but this has worked well.

cheers, mike

Edited mike (May 4, 2005 15:01:51)

Sorry for all the email asking for your pic code. I realize that you have not gotten it into a distributable fashion yet.

My motivation for asking is as follows:

I am in the process of building my kegerator (still just a bunch of parts and a chest freezer). I do not want to go out and buy a separate temp controller - since eventually the pic would control this (trying to conserve money). My understanding of your architecture is that the pic is a slave to the computer - samples temperature, communicates to computer, computer makes temperature decision, and computer communicates to pic to turn freezer on/off. Is this correct? If so, I would like to attempt to add the additional logic so that the pic can operate in Standalone mode - regulate the freezer temperature by itself (targeting some default temp). But, when a serial cable is connected and there is active communication between pic and computer - the pic would communicate with computer and rely on it to make the decision. The advantage to this approach is that I could build my kegerator it two stages: 1) freezer operated by pic w/o computer backend 2) add computer. This also would be advantageous if the computer ever got hung up, crashed, or needed to be pulled down for maintenance - the pic would resume control of the freezer and keep things at the right temperature until the computer is repaired.

What do you think of this logic? Forgive me if it is already on your list or if it already exists. If you could send me an unofficial version of the Pic code (asm, basic, or C) - I would like to attempt to add this.

Matt

Edited mwsmith78 (May 10, 2005 20:43:58)

Hey Matt,

A good idea -- it's been high on the priority list for a long time. You'll find some reference to it somewhere on the project page, basic idea being you don't need the computer to survive

I've been using pretty much the same firmware on the PIC for a long time, without the PIC handling the temperature control, because it's worked -- but it's something I've wanted to fix for a long time. I'm ready to try and make it work, though; I've got the code for talking to the 1820 visualized, just gotta try it. The PIC has a comfy amount of EEPROM onboard, so you could store small event histories or alarm temperatures here, etc.. I'd also really like a buzzer on the board to sound an alarm if things are getting too hot/cold, but I think that will wait...

I'll see what I can do this weekend and post up the code whatever the outcome is.

cheers, mike

Edited mike (May 13, 2005 15:48:51)