LinkMeter v2 Homebrew BBQ Controller - Part 2


 
Several of us just bought the wires with the crimped ends on them. Not much more expensive and worked very well. 6" F-F from Pololu worked great.
http://www.pololu.com/catalog/product/1800


Originally posted by J. Winn:
Hi guys, I'm eager to get started on this project.I just have a few questions

Also, are the connectors and crimp pins needed available on digikey or mouser? The crimp pins are backordered on Pololu and I'm going to be ordering from mouser and digikey it would be nice to be able to get everything from one of these two places.
Click to expand...
 
Oh that would have been nice to know about before I made a whole bunch of them at work yesterday. Oh well, now I know!
icon_smile.gif

Originally posted by Neil Mager:
Several of us just bought the wires with the crimped ends on them. Not much more expensive and worked very well. 6" F-F from Pololu worked great.
http://www.pololu.com/catalog/product/1800


<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by J. Winn:
Hi guys, I'm eager to get started on this project.I just have a few questions

Also, are the connectors and crimp pins needed available on digikey or mouser? The crimp pins are backordered on Pololu and I'm going to be ordering from mouser and digikey it would be nice to be able to get everything from one of these two places.
Click to expand...
</div></BLOCKQUOTE>
 
Originally posted by Matthias B:
I'm wondering if its possible to use PT100 sensors and how much work it would be to make them running?
Click to expand...
There'd have to be a code change to perform the proper calculation, which wouldn't be terribly difficult to implement as a new probe type. Theoretically it is possible but the small resistance change per degree C might prove difficult to measure accurately. Are there premade PRT probes for use in this sort of application?
 
Does it matter what probes from Maverick are used? There are a lot of model numbers on their site.

ET-732 Food Probe $20.00
ET-732 Smoker Probe $20.00
ET-71/ ET-73/ ET-77/ ET-901 FOOD Probe $12.00
ET-73 Smoker Probe $12.00
ET-7/ ET-72/ ET-902 Probe $12.00
ET-72/73 High Heat 6ft Food Probe $17.00
ET-8 Series Probe $12.00
ET-85 Probe $12.00
OT-03 / OT-3BBQ Probe $12.00
ET-74 Probe $12.00
ET-705 Probe $12.00
ET-903 Probe $12.00

I'd like to buy the ET-732 Food and Smoker Probes since they are longer but just want to make sure they will work. Or should I just get all the High Heat 6ft ones since it says those can be used in place of the Smoker probe.
 
Originally posted by Daniel Schoonover:
Does it matter what probes from Maverick are used? There are a lot of model numbers on their site.

ET-732 Food Probe $20.00
ET-732 Smoker Probe $20.00
ET-71/ ET-73/ ET-77/ ET-901 FOOD Probe $12.00
ET-73 Smoker Probe $12.00
ET-7/ ET-72/ ET-902 Probe $12.00
ET-72/73 High Heat 6ft Food Probe $17.00
ET-8 Series Probe $12.00
ET-85 Probe $12.00
OT-03 / OT-3BBQ Probe $12.00
ET-74 Probe $12.00
ET-705 Probe $12.00
ET-903 Probe $12.00

I'd like to buy the ET-732 Food and Smoker Probes since they are longer but just want to make sure they will work. Or should I just get all the High Heat 6ft ones since it says those can be used in place of the Smoker probe.
Click to expand...

Coefficients are built in for the 73 and 732 so if you stick with those, you'll be safe.
 
Originally posted by RJ Riememsnider:
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Daniel Schoonover:
Does it matter what probes from Maverick are used? There are a lot of model numbers on their site.

ET-732 Food Probe $20.00
ET-732 Smoker Probe $20.00
ET-71/ ET-73/ ET-77/ ET-901 FOOD Probe $12.00
ET-73 Smoker Probe $12.00
ET-7/ ET-72/ ET-902 Probe $12.00
ET-72/73 High Heat 6ft Food Probe $17.00
ET-8 Series Probe $12.00
ET-85 Probe $12.00
OT-03 / OT-3BBQ Probe $12.00
ET-74 Probe $12.00
ET-705 Probe $12.00
ET-903 Probe $12.00

I'd like to buy the ET-732 Food and Smoker Probes since they are longer but just want to make sure they will work. Or should I just get all the High Heat 6ft ones since it says those can be used in place of the Smoker probe.
Click to expand...

Coefficients are built in for the 73 and 732 so if you stick with those, you'll be safe. </div></BLOCKQUOTE>

Is the only real difference of those the fact that the "high heat" can deal with higher temps? I had a smoker probe that just stopped working possibly due to high heat.
 
Originally posted by J. Winn:
First the BJT(BC33725BU), is out of stock at both Mouser and digikey.

Another thing, I will probably need a larger blower for my side fire box unit. I was thinking around 20CFM.

Also, are the connectors and crimp pins needed available on digikey or mouser?

Lastly, I'm a bit confused about the "wireless probes".
Click to expand...
Any BC337 variant with an hFE greater than like 50 should work. The transistor is sort of oversized just for driving the LCD backlight so almost any general-purpose will work, including an 2N2222 if you turn it around backwards. This BC337-40 looks even better than the -25 actually.

Larger fans have been used with various degrees of success the only issue being if the 12V supply can handle it without browning out the router or creating too much noise for the serial port to operate error-free. I don't know how large the largest working blower is though.

The crimp pins, glorb I wish they were available somewhere else. I can't find them or the rectangular housings in the Mouser catalog. I've tried several items that looked like they might be the right part but never found anything close enough to use. If you can find them, it would be pretty sweet.

The wireless probes are basically a unit like this with a AA booster board attached and a place to plug a probe in. I've never really built one other than the test transmitter that spits out ambient temperature to my LinkMeter. There hasn't been a whole lot of interest. The HeaterMeter software is limited to using 4 total probes be they hard-wired or wireless because that seemed like a good number at the time. However, the rotating display, menu system, configuration, and web page is all written to fit with 4 total probes so changing that would require a lot of re-jiggering of code and displays. As far as the hardware goes, you can add it later if you want though. It does save a lot of hardware/shipping costs considering the RFM12B is like $10/ea shipped.
 
Originally posted by Daniel Schoonover:
Does it matter what probes from Maverick are used? There are a lot of model numbers on their site.
Click to expand...
I know the ET-72/3 and the ET-732 are different internally but we have builtin coefficients for each of them. I use a combination of ET-72 and ET-72 high heat. I like the high heat because they have the longer 6ft cords which is plenty long for me. One of my ET-72s are left over from a Maverick I originally owned, and I like having all the coefficients the same even though it is pretty easy to change them now. The regular ET-72s are much shorter, maybe 3ft?
 
Originally posted by Bryan Mayland:
Any BC337 variant with an hFE greater than like 50 should work. The transistor is sort of oversized just for driving the LCD backlight so almost any general-purpose will work, including an 2N2222 if you turn it around backwards. This BC337-40 looks even better than the -25 actually.

Larger fans have been used with various degrees of success the only issue being if the 12V supply can handle it without browning out the router or creating too much noise for the serial port to operate error-free. I don't know how large the largest working blower is though.

The crimp pins, glorb I wish they were available somewhere else. I can't find them or the rectangular housings in the Mouser catalog. I've tried several items that looked like they might be the right part but never found anything close enough to use. If you can find them, it would be pretty sweet.

The wireless probes are basically a unit like this with a AA booster board attached and a place to plug a probe in. I've never really built one other than the test transmitter that spits out ambient temperature to my LinkMeter. There hasn't been a whole lot of interest. The HeaterMeter software is limited to using 4 total probes be they hard-wired or wireless because that seemed like a good number at the time. However, the rotating display, menu system, configuration, and web page is all written to fit with 4 total probes so changing that would require a lot of re-jiggering of code and displays. As far as the hardware goes, you can add it later if you want though. It does save a lot of hardware/shipping costs considering the RFM12B is like $10/ea shipped.
Click to expand...

Thanks! Hopefully someone with a smoker similar to mine that has a larger blower will chime in. Thanks again!
 
Thanks! Hopefully someone with a smoker similar to mine that has a larger blower will chime in. Thanks again!
Click to expand...

Rocks Barbeque recommends a 10 cfm "For use with large backyard cookers and competition cookers" and 25cfm "For use with large off-set type cookers".

Wish they gave some actual dimensions.
 
Originally posted by Daniel Schoonover:
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by RJ Riememsnider:
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Daniel Schoonover:
Does it matter what probes from Maverick are used? There are a lot of model numbers on their site.

ET-732 Food Probe $20.00
ET-732 Smoker Probe $20.00
ET-71/ ET-73/ ET-77/ ET-901 FOOD Probe $12.00
ET-73 Smoker Probe $12.00
ET-7/ ET-72/ ET-902 Probe $12.00
ET-72/73 High Heat 6ft Food Probe $17.00
ET-8 Series Probe $12.00
ET-85 Probe $12.00
OT-03 / OT-3BBQ Probe $12.00
ET-74 Probe $12.00
ET-705 Probe $12.00
ET-903 Probe $12.00

I'd like to buy the ET-732 Food and Smoker Probes since they are longer but just want to make sure they will work. Or should I just get all the High Heat 6ft ones since it says those can be used in place of the Smoker probe.
Click to expand...

Coefficients are built in for the 73 and 732 so if you stick with those, you'll be safe. </div></BLOCKQUOTE>

Is the only real difference of those the fact that the "high heat" can deal with higher temps? I had a smoker probe that just stopped working possibly due to high heat. </div></BLOCKQUOTE>

Supposedly, although I've never had a 73 probe fail and have had 2 732s go bad.
 
Originally posted by Bryan Mayland:
Larger fans have been used with various degrees of success the only issue being if the 12V supply can handle it without browning out the router or creating too much noise for the serial port to operate error-free. I don't know how large the largest working blower is though.
Click to expand...

Is it just a question of the power supply providing enough current? If that is the issue, couldn't a different 12V supply with a higher current rating just be used, or is the noise still a problem?
 
Originally posted by Bryan Mayland:
WOW We have our own subforum now? I couldn't find the thread then got all confused.

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by RJ Riememsnider:
Bryan, I think my post got lost. How hard is it to switch to TTYS0? This is for a non-tech savvy friend and I'm worried it may cause issues for later linikmeter firmware upgrades. Your thoughts???
Click to expand...
If you use the configuration backup, it saves all the config changes needed to set it back up. I use ttys0 and it hasn't been an issue upgrading the firmware since I backup, upgrade the firmware, restore the backup, reboot. It is pretty easy:

-- Disable the serial login capability, which eats the data coming into ttyS0. SSH into the router and `vi /etc/inittab`. Make sure these two lines are commented out (start with #).
#ttyS0::askfirst:/bin/ash --login
#tty1::askfirst:/bin/ash --login

-- Tell linkmeterd/hmdude to use ttyS0
uci set lucid.linkmeter.serial_device=/dev/ttyS1
uci commit lucid

-- Reboot! The software is now all set up.

-- Hardware-wise, what I did was use wire cutters to cut the ttyS1 TX/RX pins at the 90 degree bend, then soldered some small wires from the ttyS0 holes to the pin nubs that connect to the HeaterMeter. I had a 2x1 pinheader in the ttyS0 hole and just connected to that but you can just solder them into the holes directly. You can kinda see the hack job in this picture. </div></BLOCKQUOTE>

Bryan, sorry, this didn't work for me. There must be something else going on. Can you tell me a procedure for testing on the linux side if I apply a loopback to the serial port? I assume I telnet to ttyS01 somehow and look for a duplicate char string when I enter text?

And to put this back do I simply remove the # in inittab and do:
uci set lucid.linkmeter.serial_device=/dev/ttyS0
uci commit lucid
Restart


In looking at this, is that correct?
Does uci set lucid.linkmeter.serial_device=/dev/ttyS1 set the serial to ttyS0? I tried both S0 and S1 and neither seems to work.
 
Originally posted by RJ Riememsnider:
Bryan, sorry, this didn't work for me. There must be something else going on. Can you tell me a procedure for testing on the linux side if I apply a loopback to the serial port? I assume I telnet to ttyS01 somehow and look for a duplicate char string when I enter text?

And to put this back do I simply remove the # in inittab and do:
uci set lucid.linkmeter.serial_device=/dev/ttyS0
uci commit lucid
Restart


In looking at this, is that correct?
Does uci set lucid.linkmeter.serial_device=/dev/ttyS1 set the serial to ttyS0? I tried both and neither seems to work.
Click to expand...
Oops yes I dunno how I messed that up but it is supposed to be `uci set lucid.linkmeter.serial_device=/dev/ttyS0` not S1. First check /etc/config/lucid to make sure the serial_device is set to ttyS0. Next you can try the loopback by tying the TX/RX lines together on the serial port (with the HeaterMeter not attached, and lucid stopped) and in one terminal you type `cat /dev/ttyS0` and in the other type `echo HELLO > /dev/ttyS0` and you should see HELLO come out in the other terminal. If that does or doesn't work then you can maybe see if there's something else with the port open that's eating the data

cd /proc
ls -lR 2>/dev/null | grep /dev/ttyS0

If that returns anything, then post the output of your `ps` and maybe I've forgotten something that will open the port. You might also just try `cat /dev/ttyS0` with the HeaterMeter attached and lucid not running to see if you're getting the updates every 2 seconds.
 
Originally posted by Neil Mager:
I used heatermeter.cpp.hex, renamed it to hm.hex and ran avrupdate and it worked - I connected my pit probe up and got a temperature reading!

I put together a picasa album building up the board. It roughly coincides with Bryans steps here: http://tiny.cc/jmqrfw

Picasa Album - http://tiny.cc/bnqrfw

Bryan - if any of these will help with the wiki, feel free to use them.

Now to solder up the probe jacks and mount the lcd display.
Click to expand...

Thanks Neil. I'm just getting ready to begin the project; I think I have all the parts now and ready to start soldering once my Hakko 888 arrives. The photos are exactly what I needed...very helpful. Thanks.
 
cd /proc
ls -lR 2>/dev/null | grep /dev/ttyS0

If that returns anything, then post the output of your `ps` and maybe I've forgotten something that will open the port. You might also just try `cat /dev/ttyS0` with the HeaterMeter attached and lucid not running to see if you're getting the updates every 2 seconds.
Click to expand...

This is all i got:
lr-x------ 1 root root 64 Sep 8 15:56 3 -> /dev/ttyS0
lr-x------ 1 root root 64 Sep 8 15:56 3 -> /dev/ttyS0
root@OpenWrt:/proc#


I just can't believe that both serial ports are bad....
 
The output of PS:

root@OpenWrt:/proc# ps
PID USER VSZ STAT COMMAND
1 root 1480 S init
2 root 0 SW [kthreadd]
3 root 0 SW [ksoftirqd/0]
4 root 0 SW [kworker/0:0]
5 root 0 SW [kworker/u:0]
6 root 0 SW [rcu_kthread]
7 root 0 SW< [khelper]
30 root 0 SW [sync_supers]
32 root 0 SW [bdi-default]
34 root 0 SW< [kblockd]
88 root 0 SW [kswapd0]
89 root 0 SW [fsnotify_mark]
105 root 0 SW [mtdblock0]
110 root 0 SW [mtdblock1]
115 root 0 SW [mtdblock2]
120 root 0 SW [mtdblock3]
125 root 0 SW [mtdblock4]
134 root 0 SW [kworker/0:1]
340 root 0 SWN [jffs2_gcd_mtd3]
439 root 0 SW< [cfg80211]
474 root 1492 S /sbin/syslogd -C16
476 root 1472 S /sbin/klogd
478 root 800 S /sbin/hotplug2 --override --persistent --set-worker
652 root 1484 S /sbin/udhcpc -t 0 -i eth0.1 -H OpenWrt -b -p /var/ru
819 root 0 SW [kworker/u:2]
827 root 0 SW [irq/4-b43]
859 root 1296 S hostapd -P /var/run/wifi-phy0.pid -B /var/run/hostap
966 root 1132 S /usr/sbin/dropbear -P /var/run/dropbear.1.pid -p 192
1017 nobody 936 S /usr/sbin/dnsmasq -K -D -y -Z -b -E -s lan -S /lan/
1030 root 1472 S /sbin/watchdog -t 5 /dev/watchdog
1034 root 1484 S /usr/sbin/ntpd -n -p 0.openwrt.pool.ntp.org -p 1.ope
1244 root 1196 S /usr/sbin/dropbear -P /var/run/dropbear.1.pid -p 192
1245 root 1488 S -ash
1250 root 1196 S /usr/sbin/dropbear -P /var/run/dropbear.1.pid -p 192
1251 root 1488 S -ash
1284 root 1472 S cat /dev/ttyS0
1285 root 1480 R ps
 
I was looking on the BBQ guru website for their blower recommendations and they are saying a 25CFM blower for all side fire box units. What to do...
 
Ok, so far the only combination I get any output on is HM->ttyS1

ttyS0 rx seems dead and I don't get anything when I connect S1 rx to S0 tx or S1 tx. Either some process owns the tx or both ports are dead.
 
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