💬 Stamp size MySensor node

[carlierd]

Very good ! So small !
I really need to learn how solder SMD part ! More and more design are using small components.

[sundberg84]

Well done! Nice!

[macieiks]

Hello,

I have a question about the dimensions. Could you tell me what is the exact measure when fully assembled with nrf24 and with / without goldpins? I have tiny, transparent boxes and curious if I can fit them inside :D

[GertSanders]

@macieiks

The pcb itself is 21 mm wide and 23 mm long.

With the radio the longest side becomes 30 mm long and 21 mm wide.

Without any pins mounted, the board is just under 5 mm think.

If the dual row angled headers are mounted, the longest side (30 mm with radio) becomes 39 mm.
You will need to add the length of the contacts + wire to that for a complete length.

You can also turn the dual row angled header inwards (towards the radio), then the maximum length is still 30 mm.

[NeverDie]

@GertSanders What is the difference between the v1 version of your stamp size mysensor node that's on OSH PARK and the V2 version that's on your website that you linked to in your OP ( https://www.openhardware.io/view/76/Stamp-size-MySensor-node )?

[GertSanders]

@NeverDie
None. The plan was to enhance it, so I copied my version 1 to version 2. But then I decided to publish it in Openhardware anyway.
This board is a proof of concept for me.
My next version will have a 8Mhz crystal. The addional powerconsumption is negligable bit the accuracy of timing is much better (and constant, even with dropping voltage).
So the board on OSH Park is identical to the one on Openhardware.io

[NeverDie]

Thanks! I ordered it yesterday from OSH PARK, so good to hear.

Have you found something where you really do need the 8mhz crystal oscillator, or were you adding it as a "just in case"?

[GertSanders]

@NeverDie
I have a use case where I need the clock to be acurate. For realy low power nodes like the ones with reed switches, I also prefer the internal oscillator.

[alexsh1]

@GertSanders

Goedenavond Gert,

What's your boards.txt file is saying please? I uploaded the bootloader (optiboot_atmega328_08M_038400_D8) and all went OK until I upload my first sketch.
After that I am getting:

avrdude: stk500_getsync() attempt 1 of 10: not in sync: resp=0x32
avrdude: stk500_getsync() attempt 2 of 10: not in sync: resp=0x0f
avrdude: stk500_getsync() attempt 3 of 10: not in sync: resp=0xfb
avrdude: stk500_getsync() attempt 4 of 10: not in sync: resp=0x32
avrdude: stk500_getsync() attempt 5 of 10: not in sync: resp=0x0f
avrdude: stk500_getsync() attempt 6 of 10: not in sync: resp=0x73
avrdude: stk500_getsync() attempt 7 of 10: not in sync: resp=0xff
avrdude: stk500_getsync() attempt 8 of 10: not in sync: resp=0x32
avrdude: stk500_getsync() attempt 9 of 10: not in sync: resp=0x0f
avrdude: stk500_getsync() attempt 10 of 10: not in sync: resp=0xfb

I have to upload the bootloader again in order to upload the sketch - something is clearly not working. This is my extract from boards.txt:

BlueBoard.menu.mhz.8Mhz= 8Mhz - internal oscillator D8 LED for atmega328-tqfp
BlueBoard.menu.mhz.8Mhz.bootloader.low_fuses=0xE2
BlueBoard.menu.mhz.8Mhz.bootloader.high_fuses=0xDE
BlueBoard.menu.mhz.8Mhz.build.f_cpu=8000000L 
BlueBoard.menu.mhz.8Mhz.upload.speed=38400
BlueBoard.menu.mhz.8Mhz.bootloader.file=myoptiboot/optiboot_atmega328_08M_038400_D8.hex

[GertSanders]

@alexsh1

Here is my extract for this type:

32PinBoard.name=atmega328p based - 32 pin TQFP

32PinBoard.upload.tool=arduino:avrdude
32PinBoard.upload.protocol=arduino
32PinBoard.upload.maximum_size=32256
32PinBoard.upload.maximum_data_size=2048

32PinBoard.bootloader.tool=arduino:avrdude

32PinBoard.bootloader.unlock_bits=0x3F
32PinBoard.bootloader.lock_bits=0x0F


32PinBoard.build.core=arduino:arduino
32PinBoard.build.mcu=atmega328p

32PinBoard.build.board=AVR_GERTSANDERS32PinBoard
32PinBoard.build.variant=32PinBoard

32PinBoard.menu.bod.4v3=4V3
32PinBoard.menu.bod.4v3.bootloader.extended_fuses=0x04
32PinBoard.menu.bod.2v7=2V7
32PinBoard.menu.bod.2v7.bootloader.extended_fuses=0x05
32PinBoard.menu.bod.1v8=1V8
32PinBoard.menu.bod.1v8.bootloader.extended_fuses=0x06
32PinBoard.menu.bod.off=Disabled
32PinBoard.menu.bod.off.bootloader.extended_fuses=0x07
32PinBoard.menu.mhz.8Mi-38K4-D8= 8Mhz - internal - 38K4 - D8
32PinBoard.menu.mhz.8Mi-38K4-D8.bootloader.low_fuses=0xE2
32PinBoard.menu.mhz.8Mi-38K4-D8.bootloader.high_fuses=0xDE
32PinBoard.menu.mhz.8Mi-38K4-D8.build.f_cpu=8000000L 
32PinBoard.menu.mhz.8Mi-38K4-D8.upload.speed=38400
32PinBoard.menu.mhz.8Mi-38K4-D8.bootloader.file=myoptiboot/optiboot_atmega328_08M_038400_D8.hex

[alexsh1]

@GertSanders OK, the issue is in pins_arduino.h in 32PinBoard folder. The standard file is just not good. I'll have to find the right one for tqfp chip.

EDIT: copied the "eightanaloginputs" variant in the variant folder, but still can only upload the first sketch after the bootloader, all other uploads are giving me "avrdude: stk500_getsync() attempt x of 10: not in sync:"

[alexsh1]

@GertSanders Gert, what pins_arduino.h are you using for this board please? Can you post it here?

[GertSanders]

@alexsh1

Here is the pins_arduino.h file for the 32pin TQFP package

0_1465854245099_pins_arduino.h

[GertSanders]

@alexsh1

And here is a ZIP file with my complete atmega328p definitions

0_1465854396475_atmega328p.zip

[alexsh1]

@GertSanders Many thanks for your help. This is probably my bad luck, but I have mixed up C1 and R1 mounting them vertically (not horizontally). What a stupid mistake really given that I have checked it a few times. Anyway, now everything is working.

FYG, I looked at your pins_arduino.h - this is a standard one and it is not correct. I corrected the following entries:

static const uint8_t SS   = 14;
static const uint8_t MOSI = 15;
static const uint8_t MISO = 16;
static const uint8_t SCK  = 17;

static const uint8_t SDA = 27;
static const uint8_t SCL = 28;
#define LED_BUILTIN 8

static const uint8_t A0 = 23;
static const uint8_t A1 = 24;
static const uint8_t A2 = 25;
static const uint8_t A3 = 26;
static const uint8_t A4 = 27;
static const uint8_t A5 = 28;
static const uint8_t A6 = 19;
static const uint8_t A7 = 22;

[GertSanders]

@alexsh1
OK, I will check also on my side :-) Thanks for the feedback.

[alexsh1]

@GertSanders No worries! And signing works flawlessly on this node as well with ATSHA204A by the way :)

[alexsh1]

[GertSanders]

@alexsh1
Double plus good !
As I have no signing capability on my raspberry-turned-gateway I'm glad the hard work to simplify signing was done so well by @tbowmo and @Anticimex. Even without testing it I could assume it would work.

[Anticimex]

@GertSanders You are welcome :) Btw, if you just patch in support to generate random data for a nonce, you can use the soft signing backend on rPi.