LinkMeter v2 Homebrew BBQ Controller - Part 2


 

Bryan Mayland

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Me too. Do you have an RFM12B chip installed or is it without RF? It's the only thing I can think of that could cause things to go wonky.
 
Nope, no wireless. It was fine, and I was clicking around setting stuff up and suddenly it wasn't. I had never actually had a button hooked up to either of my builds so I was unaware of the reset config option till you brought it up! Thing is humming right along now.
 
Hey Bryan, what is the current state of linkmeter/heatermeter 3.2? I see the code was updated a week or 2 ago but I'm having trouble getting my linkmeter updated and seeing my heatermeter, is there a current howto or place I can look for changelog, etc....?

EDIT** I did get it flashed with mtd but am still wondering where the best place for status is.....**
 
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Bryan Mayland

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The changelog is available through the github commit history. The WRT54GL target (bcm47xx) and the rPi target (brcm2708) have the same changes, but some things just don't work in the WRT version (like alarm scripts). Every so often I build and test a new image and if it appears to work I push it out the my download snapshot site.

I'm not really sure what the update procedure is. It is supposed to be "use sysupgrade" but that generates an invalid image checksum so it often does not work, and the website just uses that on the backend so it doesn't work either. I've only had luck with the tftp-style fresh installs.
 
Thanks Bryan, I am about to give up, I'm now having the same serial port issues that have happened to me several times where the TX on the router stops sending so the HM es essentially read only. may be tiome to switch to the 4.0.
 

Jarrod Igou

TVWBB Member
If you've got the thermistor soldered onto the FOOD3 probe jack as in the schematic, then you should get something when you unplug a probe. To get it to read ambient temperature just change the coefficients for it to the Vishay 10k.

If you don't have the thermistor, it should blank out if nothing is plugged in. You can check the voltage at the probe jack pin and it should be 5V with nothing plugged in.

Sooooo.....the Vishay 10k thermistor. I've seen the data sheet. I don't see the coefficients that the heatermeter config needs, though....

Am I missing what I need, or (even better) anyone have the numbers I need to plug in so I'm not reading 207 degrees ambient?

Thank you!!!

Jarrod
 

Bryan Mayland

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Under the probe coefficients, use the presets link then select Vishay 10k. Those should be for that thermistor I believe. If not then I've messed something up along the way. I bought a bunch of different thermistors and they're really hard to identify once they're out of their little mouser bags so there is a possibility I've gotten them mixed up at some point.
 
While I'm waiting on my 4.0 parts I decided to play with the HM3.2 board and try to just make a standalone PID. Is there a way to edit coefficients and other settings usually only available via the linkmeter? ie, is there a standalone version of the sketch that I'm just not finding?
 

Bryan Mayland

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Yeah LinkMeter just sends HeaterMeter SET commands, the list of which can be found in the README.txt or the list in the Wiki's command page. You can just use any TTL serial cable (FTDI, or one of those phone cables) to send the commands over serial. I try to keep them up to date so let me know if you come across something that's not documented properly.
 
Bryan,

Have you considered tying together the "time to 180/200F" and the alarm thresholds? Meaning, I typically set the high alarm on my meat probes to whatever I want the final temperature to be, so I get paged if I am not paying attention or whatever. While I can guesstimate the time it will take a chicken to finish cooking to 165F based off the 180F figure, I thought maybe it would be cool if you had a high alarm set that it would use that as the basis for the time to finish numbers.
 

Bryan Mayland

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I have! Thanks for reminding me. When I first added that I thought it would go well with the alarm limits. I'll have to add that now.
 

Riku Naskali

TVWBB Member
Will LM work without the latch register and LCD? I had it all working, crammed everything inside the Linksys case and got some smoke out of the latch register :eek:

So I desoldered the latch register.
 

D Peart

TVWBB Pro
that shouldn't impact using the web interface, you just won't be able to use the 4-way button very easily.

You do know that electronics are all just smoke and mirrors. If you let the smoke out they won't work anymore . . .

dave
 

Riku Naskali

TVWBB Member
that shouldn't impact using the web interface, you just won't be able to use the 4-way button very easily.

You do know that electronics are all just smoke and mirrors. If you let the smoke out they won't work anymore . . .

dave

That's okay,

I never had that 4-way button in there, anyway :)
 

Riku Naskali

TVWBB Member
Started assembly of the Heatermeter 4 :)

Is there a reason why there isn't a dip socket for the latch register? Would be easier to replace if I fried it again ;)
 
Started assembly of the Heatermeter 4 :)

Is there a reason why there isn't a dip socket for the latch register? Would be easier to replace if I fried it again ;)

The lineout connector from the RPi on my board is right next to the latch register, if it was higher, the RPi wouldnt fit anymore for me. Think that is the problem
 

 

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