Heater Meter V4.2.3 build questions


 

RalphTrimble

TVWBB Diamond Member
OK, got my HMv4.2.3 board nearly built up tonight but have a few questions.

On the image below, do I need to put jumpers where I drew the (8) red lines (2 per probe I assume)?

Next, it looks like there should be a capacitor below each pair of those jumpers? What value cap should go there? (where I traced out the red boxes)

Also, What does the "10K, 100K, 0.1u" mean where I have drawn the red box? (maybe I have answered my own questions below, please confirm if I am on the right track)

HMv4.2.3.jpg


Looking at the schematic I see (4) 100K resistors in series with the probe leads, so I gather they are the R in the RC filters you added to the probes? Does that mean I should not be using the jumpers where I drew the red lines, and should put in a 10K, 100K, and .0.1u cap in those (4) spots instead of jumpers if I want to have the RC filters? Also assuming these resistors would need to be installed standing upright, and the (4) 10K resistors in that group are the pullup resistors for the probes (and are not optional)?

I don't have a 68K resistor here in my parts order, and don't see it on the HMv4.1 BOM either. It wasn't marked as a new part on your HMv4.2.3 BOM so I didn't order it....

The same goes for the 100K resistor (that you noted I should use in place of the 22K that I crossed out), I don't see it on the 4.1 BOM and it wasn't marked as a new part on the 4.2.3 BOM.

In addition to the above mentioned 100K resistor, I see the 4.2.3 BOM lists 4 more 100k resistors (R22, R23, R28, R29). They are not shown on the 4.1 BOM and weren't noted as a new component on the 4.2.3 BOM.

If you send anyone else a 4.2.3 board you should note the above mentioned resistors a new part that need to be added/ordered, and note that they should order extra 0.1u caps as well....


Finally, on mounting the LCD, when looking at the button side of the HM board, should the LCD board be under the HM board or on top?.... and the LCD and HM boards are supposed to sit right on top of each other (no space between them), correct?

I guess I wont be getting this board together until the end of the week at best, cause I ran short on 0.1u caps cause there are so many more used on this board, and I need to order those few resistors mentioned above as well. I don't have much faith in Radio Shack carrying these parts, they seem to carry very little electronics these days, they probably have more phones than resistors and caps... lol .... but I will stop in there tomorrow to see if I can find the caps at least, I've got a box of misc resistors and I bet I could find what I am missing in there if I dig, but wont have those caps....
 
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There's not enough space on the board do put the labels on those groups of components you put all the red lines on, the text in the little box is the "key" to what goes in each little box by each probe. Top to bottom: 10k, 100k, 0.1u. 10k is the 10k 1% pullup, 100k is the R in the RC filter, 0.1u is the C in the RC filter. They need to be mounted vertically to fit and they're all pretty much required, except for the thermocouple jack. I think you said you've soldered in the thermocouple amp, so leave the 10k off the pit jack.

I didn't provide links/part numbers all the new parts on the BOM, just ones I thought would be harder to find or would need parts for. The 68k is on line 19. You're right about the 100k resistors, the bom lists 4 and there should be 5x 100k and one fewer 22k (R19). Sorry I wasn't clearer about about what was new, I figured you'd check the list versus what you had on hand.

The LCD does mount below the HeaterMeter board, with them sitting flush together.

There's a firmware build on the snapshots that has the noise lockout removed. In your testing, pay attention to when you plug in or unplug a probe and let me know if you see any single reading during the plug event that's way off (like the value wasn't settled before reading).
 
Frys has them all. you are not far I can give ya .1u caps

Nice that you have a Fry's by you, but its about an hour away from me and I don't have the time this week to drive two hours to get a few capacitors, I'd rather just order from Mouser and go to my mailbox. I'm occupied all day tomorrow anyways and might not be able to get back to this project on Thursday, so unless Radio Shack has the caps today it's gonna have to sit on hold for a while....

Bryan, thanks for answering my questions. This is an unfamiliar board to me and without build instructions or pictures I was left with those few questions. I think I got it all figured out now, thanks again....
 
Bryan, I was looking over the parts list getting ready to place my order for stuff that I am missing....
For some reason the DC-DC converter description caught my eye, it says it is a "Non-Isolated" DC-DC converter... This got me to thinking, perhaps if we used an isolated DC-DC converter instead that would remove the potential to ground and eliminate the problems when you touch the probe leads while barefoot? What do you think?
 
I'm not sure because I've never tried, but an isolated DC-DC converter for 5V 1A is about 1.6"x1.0" and $15 so both those specs are a little outside our parameters. I'm wondering if there is a tiny 1-to-1 transformer that can be used to isolate the 3.3V section of the HeaterMeter. I don't think that would work because the I/O to the Pi wouldn't have a common ground any more.

The other option is finding a cheap isolated 12V 1A supply, which I can't really seem to do. You can get one of those cheap power supplies too but they're not exactly tidy.
 
Well, I was thinking the isolated DC-DC 5V regulator would isolate the electronics from real ground (that you touch with your feet etc), but leave the 3.3V and 5v on the same "lifted" ground, since the 3.3v is regulated from the 5v. I would guess the reason for the larger size of the isolated unit is some sort of transformer, no matter how you slice it a transformer is gonna be a large-ish item compared to most of the parts in the HM....
Just thought I would throw that idea out there after I noticed the DC-DC we are using is non-isolated, which made me realize there must be other versions that are isolated... How much current on the 5v line do we need to run the HM?
 
There's a firmware build on the snapshots that has the noise lockout removed. In your testing, pay attention to when you plug in or unplug a probe and let me know if you see any single reading during the plug event that's way off (like the value wasn't settled before reading).

I just flashed the latest snapshot firmware and it didn't go well. The home page will load, but when I hit config it wont open and then I can't get back to the home page until I reboot. Not sure why, the previous snapshot with the noise lockout flashed and worked just fine... I guess I gotta pull the SD card and re-image it, will try the snapshot one more time but I am guessing I will get the same result....
 
Well, I pulled the SD card, flashed the V10 image to it, booted up and still can't get the config page to load? So I did that again, this time using the norestore option and got the same thing. Not sure what exactly is going on... So I tried to use PUTTY to connect thinking I can ty and force flash the AVR Firmware, but PUTTY connects, I enter User: root and expected blank password to work, but it didn't, so I entered the password I had set and that didn't work either. So I can't get putty to work now either.... Bad day in Heater Meter land for me I guess... LOL Suggestions welcome.... gonna see if I can find another SD card and give that a try....
 
It's been no go, no how since I flashed, so I pulled the ATMega and installed a fresh one and it is working again...
Now I am wondering how the hell I am gonna get the original ATMega back to a usable state? It seems PUTTY doesn't want to connect when there is no password set, and I can't get to the HM interface to set it or flash the AVR back to normal. I've been using SSH mode in PUTTY to connect, maybe I should try another method to get putty to connect?.... open to suggestions....
 
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I had about 5 atmega fail to program. The only way to get them back possible is to get a programmer. I have one, when I first made version 2 hm, but I forgot how to use it, lol. I'm not sure even that would work or why it happens sometimes
 
I had about 5 atmega fail to program. The only way to get them back possible is to get a programmer. I have one, when I first made version 2 hm, but I forgot how to use it, lol. I'm not sure even that would work or why it happens sometimes

Maybe mine just got flashed one too many times and said "ENOUGH ALREADY!" LOL It does seem to work, somewhat, so all hope is not lost. Now that I have verified it as the source (by substituting a new ATMega in there) I am gonna re-install it and poke at it some more... Cause I'm afraid to try and flash the snapshot release to this new mega for fear I may kill it too!

EDIT:
DUH, perhaps if I connect a monitor and keyboard directly the the rPi I can get in and force the flash of the AVR back to normal....
 
With all this shuffling and plugging/unplugging I finally did it.... Connected my router to the HM blower/servo output port that is.... The HM thinks my router is 452 degrees I guess, at least that's what it was reporting for the Pit Temp.... Thank god the router wasn't that hot! LOL It seems to still be working fine, so I guess there's your answer if you were wondering if you will burn things up if you plug into the wrong CAT5 jack. I'm kinda surprised the +12v didn't kill it, then again, with the newer blower driver circuit switching the +12v instead of the ground I guess the +12v wont be there until the blower turns on... Glad I converted over the blower driver circuit from v4.0 to v4.1 style, probably saved my router...
 
So, after starting with a freshly imaged SD Card on a brand new ATMega, got it booted and set the password. then put the original (locked up) ATMega back in and was able to log in with Putty (assuming cause I had set the password with the good ATMega installed), the HM config still wouldnt load, but I was able to flash the ATMega via Putty and now it's working again...
Now that I know how to recover from this I am gonna try and flash the snapshot again, cause I'm a glutton for punishment I guess... lol
 
Most networking gear will handle up to 48v, even on the data pairs. You'll generally be fine unless you use one of these.

etherkiller.jpg
 
Flashed the snapshot firmware again and same deal. DOA HM.... This time rather than re-imaging the SD card I went straight to PUTTY and since the config hadn't been reset I was able to login with root and my password, I used the command "avrupdate /lib/firmware/hm.hex" to reflash the ATMega and it is working again. So in retrospect re-imaging the SD Card and using the norestore option was a bad move the first time around...

With all that figured out I am back to the release firmware, and reporting that for some reason the most recent snapshot firmware is hosing up my Heater Meter....
 
Most networking gear will handle up to 48v, even on the data pairs. You'll generally be fine unless you use one of these.

etherkiller.jpg

I'm glad to know that making the mistake and plugging into the wrong CAT5 jack wont kill your equipment... I don't think I will be needing one of those network killer cables you posted the picture of! LOL
 
Ah good problem description! The problem is because the new firmware uses a different format for the debug log messages that isn't compatible with the linkmeter version you have. When HeaterMeter sends out a debug message it crashes the linkmeterd which causes you to "lock up" in that no web pages work after that (and won't work on reboot either because it just keeps crashing).

I've updated the snapshot and removed the debug logging so it should work with either linkmeter package. You're going to want to force upgrade to the development build to be able to enable TruVolt mode on your output.
 
OK, just loaded your new snapshot and it seems to be working.... What do I need to do to force upgrade to the development build exactly?
 

 

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