LinkMeter v11 and firmware


 

Bryan Mayland

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NOT LATEST SOFTWARE See the Latest v12 thread

Required for HeaterMeter v4.2 hardware features, it's time for new OpenWrt firmware including the LinkMeter v11 (package).

OpenWrt (RaspberryPi) firmware updates
  • Default to AP mode "heatermeter" for initial setup rather than leaving the wifi off. HeaterMeter is http://openwrt.lan/ or http://192.168.201.1/ on the wifi. Lan still supports DHCP client or http://192.168.200.1/
  • Home page loads faster, especially on mobile where it is easily twice as fast.
  • norestore option now works properly if using windows's notepad.exe to edit cmdline.txt
  • Probe noise information displayed on home page. Don't see a yellow or red symbol on the page? That's good news! (avr+)
  • "degrees per hour" display is now calculated on the server using least squares fitting linear regression rather than simple math in the browser. Allows more accurate estimates as well as only requiring half as much data
  • webui conf page now lists the chosen probe coefficient rather than pesky numbers
  • Switching between thermocouple and internal probe types defaults the resistance and mv/C
  • Support for RT5370 usb wifi adapters
  • Added wifi-ap in addition to wifi-client shell script for easy wifi mode configuration
  • The home page is now editable by defining your own user CSS (saved across updates)
  • Home page remembers time scale and which probes are shown across sessions
  • Home page swapped sides of fan percentage and temperature on the graph, temperature now on the right
  • Home page now accepts "XX%" to set manual fan mode in addition to "-XX"
  • Include unknown probe steinhart calculation (command line only)
  • Home page no longer says "Current ..." at the top
  • Switch between pulse / voltage blower output mode (avr+)
  • Increase maximum simultaneous connections to 30 (from 10)

Update by going to System -> Backup / Flash Firmware. Paste this url in the image url (.gz) box and press the button.
http://capnbry.net/linkmeter/release/bcm2708/11/openwrt-rpi.gz

After updating go to LinkMeter -> AVR Firmware and update from the bundled hm.hex to get that as well which includes these changes.

AVR firmware update 20140630B
  • Voltage output mode for v4.2 boards
  • Freerunning ADC averages more probe samples together for better noise rejection
  • Noise range output every 4 seconds
  • More accurate thermocouple readings using dynamic reference adjustment
  • Better button debouncing for more accurate button press detection
  • Smooth servo adjustment instead of jerking to position
  • Updated the default config to use more aggressive PID constants (0, 4, 0.02, 5) and safer servo pulse durations (1000-2000us). Voltage mode is now the default fan mode for blank AVR flashes
  • Fix fan turning off or on while alarm is ringing
  • Tons of internal changes to reduce firmware size and speed many internal internals

For fresh installations, use Win32DiskImager (windows) following the instructions in the wiki. HeaterMeter 4.x Software.
 
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If you use the "Generate archive" button to create a backup, can it be restored to Linkmeter v11 and firmware? I am hoping to not have to go through all of the network, alarms and alarm script setup again.
 
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You can restore an older configuration backup on a newer system and it should work. Why not just leave "keep settings" checked though and not wipe your configuration because you'll end up at the same place? "Keep Settings" does a backup to a spare partition, installs the new firmware, then restores the backup.
 
Okay. I was confused by your comment
A few of the changes you'll only get if you choose to not "Keep settings" when updating the firmware. They're minor though, so no hard feelings if you don't wipe your device. To revert to v10, use this firmware url and then reflash the v10 AVR firmware once that's done
on this thread.

I didn't want to miss getting something. So, I thought I would have to manually backup/restore.
 
hm+error.jpg
 
Oh man, you've got Red Squggles of Death! What's so crazy about your HeaterMeter that you've got so much noise?


No idea, they are ET-723 probes with 22k resistors. It's so bad it is unsealable with a digital power supply, I have to use one with a transformer. I thought this was normal. Maybe I should take it apart and do some testing.....
 
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Did the TX-1001X-OP food probe co-efficiants get hard coded, i know the earlier version were incorrect and you supplied the correct values to enter manually.
 
Yes the... wait are they? (checks) Yes the TX-1001X preset has the right values now 6.6853001e-04,2.2231022e-04,9.9680632e-08 so they do not need to be manually entered.
 
My lines are pretty squiggly, too. I thought this was just to be expected. Now that I've upgraded, my probes almost always show a red or yellow noise icon, too. Do you have a suggestion of what I might look at to reduce the noise?

SWylbwS.png


Oh man, you've got Red Squggles of Death! What's so crazy about your HeaterMeter that you've got so much noise?
 
The squiggles you're seeing Darren are actually artifacts of the ADC resolution. The flat horizontal bits are actual full resolution points and the slopey bits are interpolated readings generated by oversampling/decimation/averaging. The spacing between the steps is dependent on which probe type it is and the divider resistor used and indicates the true resolution of the temperature reading. Do you have different probes for the Pit vs the Food?

As far as the noise:
-- if you have ET-732 probes, ground them.
-- if you have HeaterMeter v4.1 make sure you have the "white wire fix" if you haven't
-- Try a different 12V power adapter
 

 

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