My Slim 2AA Battery Node

[GertSanders]

Very nicely done ! Great idea, makes the sensor blend in. Fortunatly in Belgium we do have access to cheap cableducts. I did not think of using them as a case, but given that we have access to various widths, I will check.

May I ask, which boardhouse made the PCB's for you ?

Gert

[m26872]

@GertSanders I ordered from DirtyPCBs. It was 51mm but it didn't complain.

Hm. I can now see few strange spot in one of the PCB-photos above. I'll look into what that can be...

[aproxx]

Thanks for the detailed information about this project! I was/am looking for a similar solution to check whether doors are opened or closed.
Have you ever considered drilling a hole in the top of the door, and placing the entire node inside this drilled hole like the video below? Similar to this video?
That was something I planned to do, but your solution seems really nice as well in case drilling a hole in the door doesn't work out as expected.

[Harrdy]

I see u don't use a external 8mhz quarz. Because any technical reasons (=low current?) or for reasons of space?

[AWI]

@m26872 Great design, did you share the design on dirtyPcb's?

[m26872]

@aproxx I've never thought about it, but I think it's an excellent idea for some situations.

[m26872]

@AWI No, but the Eagle files are attached above. I'm new to all this open hw/sw sharing. You're very welcome to tell me how I should do it the right way. PM if you like.

[AWI]

@m26872 When you check out your order you can set the "sharing" options:
and even get a small profit (or a donation to MySensors..)

[scalz]

@m26872: very nice idea :smiley:
just a little question, is your cable duct pvc. I think so. Alloy maybe would not be great for radio...
yoyur idea can be very helpful thx for share.

[m26872]

@scalz Yes, it's pvc.

[m26872]

@Harrdy said:

I see u don't use a external 8mhz quarz. Because any technical reasons (=low current?) or for reasons of space?

Low power, low cost, less space, less work. Stability might be an issue at different ambient temperatures etc.

[m26872]

Added a boardhouse link if anyone would like to order the board straight from there (thx @AWI). Couldn't see any cons.
I think it's enough tested, but personally I'd wait for a tested v2.0 or make suggested improvements myself first.

[ahhk]

Hi,

great job! I think i will use your board to for small window -sensors.
But one question: i cannot upload sketches via arduino-ide when the 1mhz bootloader is flashed. i checked the wires and everything else and i tested a 8mhz/internal bootloader - works fine. but the 1mhz-bootloader just does not accept uploads?

[m26872]

@ahhk There's also the precompiled bootloader for 4800 baud in the link above. Did you try that one too? I think 9600 baud was maximum serial speed at 1MHz. Lower should be safer.
Or what do you mean with "does not accept uploads"? Is it locked?
Double checked boards.txt settings?

[ahhk]

Hi,

i can upload via RX/TX with arduino IDE with the 8mhz/internal bootloader. but if i flash the 1mhz bootloader from the link above (atmega328_1a.hex), i cannot upload the same way...

TX/RX is connected correctly. I can upload a sketch via "Upload with programmer" and receive and transmit characters with 9600baud. tested with the example-sketch "SerialEvent".

IT is a brand new 328P - not locked...

boards.txt shows

##############################################################

apm96.name=APM Optiboot internal 1MHz noBOD 9600baud

apm96.upload.tool=avrdude
apm96.upload.protocol=arduino
apm96.upload.maximum_size=32256
apm96.upload.speed=9600
apm96.bootloader.tool=avrdude
apm96.bootloader.low_fuses=0x62
apm96.bootloader.high_fuses=0xde
apm96.bootloader.extended_fuses=0x07
apm96.bootloader.path=optiboot_v50
apm96.bootloader.file=atmega328_1a.hex
apm96.bootloader.unlock_bits=0x3F
apm96.bootloader.lock_bits=0x2F
apm96.build.mcu=atmega328p
apm96.build.f_cpu=1000000L
apm96.build.core=arduino
apm96.build.variant=standard

##############################################################

i didnt try the 4800baud bootloader until now....i will do now...

[m26872]

@ahhk Reset issue? Maybe try other startup times (low fuse 42h or 52h), other usb2serial or adjust reset R and C.

[m26872]

For info. I've prototyped and ordered a slightly improved version of the pcb. Note that this is UNTESTED and experimental.
Eagle brd-file and board house link. Use it for inspiration. Don't expect it to be and tested until next month at least.

[mfalkvidd]

Great work @m26872
Thanks for sharing!

[frenchclem]

Really great idea @m26872 !!
I'm waiting for the V1.2 test and review before ordering some boards on DirtyPcb.
One Tip/question : have you thought on panelizing your slimnode, because we could easily fit 3 board on the 5X5 limitation ? I also think that DirtyPCB would even process the break routing to ease board separation.

[m26872]

@frenchclem
AAMOF I ordered a panelized version just a few days ago. I'm completely new to all this, so I leave no guarantees...
Here's the brd-file.

Edit 3/12: Boardhouse link removed (the panelized version of v1.2 contains a faulty via between D13 and SCK.)