New Build - v4.2.4 So Close! - Help Requested and Appreciated


 

ScottG

New member
Long story short, I've built the unit, checked voltages, searched forums, performed reflow, cleaned with alcohol/toothbrush - all numerous times.

Current Status:
HM powers up - green and yellow LED's illuminate, LCD works with Black Boxes
RPI working - can log via ethernet, access configuration and get infamous "No HM board", no firmware etc error. Attempt to force flash hm.hex = AVR Fuses error, cannot flash

All voltages appear to be correct except what I believe is R28, R29, and C15? I highlighted the problem pins/connections as confirmation. On the ATMEGA pin, 0.1u, and 100k, I'm measuring anywhere between .14V - .2V (depending on after resolder/reflow attempts). I can't seem to get 3.3V on any of those. I apologize if any pertinent info has been omitted and thanks in advance for any guidance.

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Steve_M

TVWBB Guru
I'm not 100% sure, but if the Atmega hasn't been flashed, then the high or low state of the pin might not be set, which is why you don't see the correct voltage.

The main concern is that you're unable to flash the Atmega chip.

If you can ssh into it and get to a shell prompt, try running this command see what it reports.

Code:
hmdude -v -v -v -v -b 128 -P/dev/spidev0.0

i'd also ensure that you're getting 3.3v out of IC4. That's what provides 3.3v to everything.

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WBegg

TVWBB Pro
Had the same problem on one of my builds. Atmega wouldn't flash. Turned out to be a bad 16mHz resonator.
 

ScottG

New member
I'm not 100% sure, but if the Atmega hasn't been flashed, then the high or low state of the pin might not be set, which is why you don't see the correct voltage.

The main concern is that you're unable to flash the Atmega chip.

If you can ssh into it and get to a shell prompt, try running this command see what it reports.

Code:
hmdude -v -v -v -v -b 128 -P/dev/spidev0.0

i'd also ensure that you're getting 3.3v out of IC4. That's what provides 3.3v to everything.

Thanks Steve..... I checked and I'm indeed getting 3.3V out of IC4. Is this the info you were wanting to see? Thinking of trying: 'run attitudeadjustment.exe'


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ScottG

New member
Had the same problem on one of my builds. Atmega wouldn't flash. Turned out to be a bad 16mHz resonator.

Forgive my ignorance, but how did you determine it was the 16mHz resonator, since it has no baseline voltage?
 

WBegg

TVWBB Pro
Forgive my ignorance, but how did you determine it was the 16mHz resonator, since it has no baseline voltage?

Trial and error, mate. I was in the same situation. Voltages looked good everywhere. Replaced the resonator and BAM, it came to life. Really no simple way to test them with simple meters.
 

Steve_M

TVWBB Guru
do you have another raspi you can try with? I have one that seemingly has a bad SPI bus and it won't flash the Atmega but everything else works. You can also try and reflow the solder on the oscillator.
 

ScottG

New member
do you have another raspi you can try with? I have one that seemingly has a bad SPI bus and it won't flash the Atmega but everything else works. You can also try and reflow the solder on the oscillator.

I considered that but held off pending other troubleshooting....I'll get another raspi and give it a shot.
 

RalphTrimble

TVWBB Diamond Member
sometimes on double sided boards like the HM you can check continuity on the solder side and find it good, but not have continuity on the component side where a trace jumps to the other side of the board and continues on. I would remove the ATMega from the socket and reflow solder on the ATmega, wiggle the leg a bit when the solder is melted to help it flow through to the other side. Same thing with the rPi header.
 

ScottG

New member
sometimes on double sided boards like the HM you can check continuity on the solder side and find it good, but not have continuity on the component side where a trace jumps to the other side of the board and continues on. I would remove the ATMega from the socket and reflow solder on the ATmega, wiggle the leg a bit when the solder is melted to help it flow through to the other side. Same thing with the rPi header.

Thanks Ralph, good tip/info....will do that and report back.
 

ScottG

New member
do you have another raspi you can try with? I have one that seemingly has a bad SPI bus and it won't flash the Atmega but everything else works. You can also try and reflow the solder on the oscillator.

Thank you everyone for the help. Steve, we have a winnah! Popped in a new RPI and heard the sweet sound of a fax modem, which I thought for a second was my HM performing it's first cook, of itself. Saw 631F pit probe temp on LCD and shut her down until I can get back at it this afternoon. Next up will be tackling the servo/damper/blower bracket attachment, but wanted to just say thanks again. I'll pour one out....err, throw a rib and some burnt ends on the ground in your honor for the first cook.

I'll continue to update the thread for the benefit of others, should I run into anymore issues.
 

Steve_M

TVWBB Guru
Thank you everyone for the help. Steve, we have a winnah! Popped in a new RPI and heard the sweet sound of a fax modem, which I thought for a second was my HM performing it's first cook, of itself. Saw 631F pit probe temp on LCD and shut her down until I can get back at it this afternoon. Next up will be tackling the servo/damper/blower bracket attachment, but wanted to just say thanks again. I'll pour one out....err, throw a rib and some burnt ends on the ground in your honor for the first cook.

I'll continue to update the thread for the benefit of others, should I run into anymore issues.

Cool. Glad to hear it's working. I assume you were joking about the fax modem sound? If not, that's a first!
 

 

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