Troubleshooting - HeaterMeter4 with Raspberry pi B


 

Shane S

New member
Ok, so the heatermeter rPi setup is fully constructed, inoperative, and my troubleshooting has not illuminated any solutions so I am throwing myself on the mercy of the forums. Here's the deal:

1) I constructed the board late one night. For whatever reason, I left out the "R7-0" strap for the LCD. I know, first step bungled, not a good sign. Moving on. I flashed "openwrt-brcm2708-sdcard-vfat-ext4_224.img" to the SD card via Win32 DiskImager, inserted into the rPi, and connected the rPi to the HM board. I did not have a microUSB cable so the initial power-up was performed with the 12V barrel connection.

2) When I powered up for the first time the top two LED's (red and yellow on my HM board) lit up solid and stayed that way for more than 2 minutes. The LCD backlight did not come on, so I powered down. I rechecked the board, realized that I was missing the R7-0 strap, soldered it in, and powered it back up. Same result.

3) Searching the forums and finding this post on a nearly identical issue, I rechecked each solder connection, reheating and adding solder when necessary. I checked the ATmega328P and made sure that it was properly seated, no pins were bent or not making contact. I also procured a microUSB cable before powering back up. Same result.

4) Concerned that I had fried the rPi before it could flash the ATmega328P, I disconnected it from the heatermeter board, connected it to a monitor & keyboard, and powered up via microUSB. OpenWrt appeared to load, but would not recognize keyboard input. I then downloaded Raspbian wheezy, flashed to SD, and powered that up on the rPi. It loaded normally and I was able to type commands, which seem to put the rPi in the clear.

5) More forum searching resulting in finding the rPi bootloader issue, so I went through the process described to replace the bootcode.bin and the start.elf with the one from wheezy before powering up the rPi again. Same result: it loads to a point, then stops and does not accept input from the keyboard. The forums seem to indicate that this is the normal stopping point, but here is a screenshot of the boot process where it freezes:


Needless to say, pressing "enter" does not have any effect.

6) Unconvinced that the rPi was really ok, I installed rasplex media center and gave it a network cable. It powered up and worked perfectly, showing the plex media library on my pc server and playing 1080p video files without fault. I think it's safe to say the rPi is fine.

My suspicion is that perhaps the OpenWrt software doesn't recognize my wireless USB keyboard. Wheezy and Rasplex being larger projects may have a more extensive peripheral driver library? I don't know. As far as the HM board, I'm stumped. By chance I discovered that with the power on, when my multimeter probes were measuring across the collector and base or base and emitter of the LCD driver (Q2), the LCD backlight turns on. Whisky. Tango. Foxtrot. I'm guessing I've got a bad Q2, but that only addresses display issue.

Is there some sort of bat-signal that I can shine in the night sky that will summon Bryan Mayland to my house? Because that would be helpful. :)
 
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Wow good post with your whole story there, with all the important details. You're absolutely right about not having the right keyboard driver. Raspbian has drivers for everything and the OpenWrt only includes drivers for "USB HID" keyboards. As you can see in your log there, your Logitech is a "USB Receiver" class which I don't have a driver for. You can either plug in a standard HID keyboard, or plug in the network and just configure everything from the web interface.
 
I had some of the same problems you have, see if you can log into RPI through the ethernet cable and see if it recognizes the HM board is connected. Im really not 100% sure what fixed mine but this is one the things Bryan reccommended and mine started working afterwards.

"If you can get that far with the HeaterMeter board connected, go to LinkMeter -> AVR Firmware -> Bundled Firmware and try flashing hm.hex to see if the Pi can see the AVR chip at all".

Not sure this will fix yours because I had enough problems of my own
 
Thanks for clearing that up Bryan. I wish there was a way to adequately express my gratitude for all your work and support on this project without resorting to cliches like "You're the man"... but you are the mother-flippin' MAN. :p

I left out the other ten paragraphs or so where I played around with configuring the rPi over the network. I was reluctant to put too much effort into that area until I could be certain that the OpenWrt software was booting properly. That'll be my next move now that the boot issue is locked down. Then perhaps some additional soldering on the top of the board connections to be double-sure that I don't have a bad connection anywhere. Will continue to post my progress for the benefit of the forum.
 
I had some of the same problems you have, see if you can log into RPI through the ethernet cable and see if it recognizes the HM board is connected. Im really not 100% sure what fixed mine but this is one the things Bryan reccommended and mine started working afterwards.

"If you can get that far with the HeaterMeter board connected, go to LinkMeter -> AVR Firmware -> Bundled Firmware and try flashing hm.hex to see if the Pi can see the AVR chip at all".

Not sure this will fix yours because I had enough problems of my own

Will do, as soon as I can get away from the office. If only I could take the afternoon off and focus on the things that really matter. :p
 
SUCCESS!!!
Where's the emoticon for "Irish Jig?"
Thanks for the help, guys!

For those still having trouble:
Most of this is in bits and pieces elsewhere in the forum, but I haven't seen the whole process laid out clearly.
Leaving aside whatever I was doing wrong last week, connecting to the rPi's OpenWrt homepage through a router is fairly straight-forward:

1) With the HM plugged into the rPi, connect both the rPi and your PC to the router's ethernet ports via network cables. Power up the rPi.

2) Change your computer's IP to be on the same subnet as the rPi. Since the rPi default is 192.168.200.1, I changed my computer IP address to 192.168.200.2. The subnet mask filled in automatically (255.255.255.0), but I also had to define the "default gateway" to point at the router connecting the two. For my router this was 192.168.1.1, which I believe is default for most home routers.

3) In your internet browser, go to the rPi's address (192.168.200.1)
If all goes well, you get this:



4) Click the configuration link down at the bottom and login when prompted, there is no password by default.

5) You should get a OpenWrt menu. Select the "AVR Firmware" tab at the top and select "Bundled firmware in /lib/firmware." It should reveal the "hm.hex" file that you're looking for with a "Flash" button to the left. Like this:




6) If all goes well, you'll be treated to a compiler window showing the progress of the rPi flashing the HM program to the ATmega328P. On my board the always-on LEDs immediately went dark, then the LCD backlight came on at 10 seconds in. Once the program finishes flashing the HM board, adjust your LCD potentiometer to fix the contrast. The words "No Pit Probe" have never looked so good, eh?

 

 

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