[DSC_1239] This is a quick and dirty sketch of a temperature sensor running on a ATtiny 85. The ATtiny internally 8Mhz oscilator devided by 8 is used. Brown-out detection is set to 1.8V. The node has a fixed datarate and channel frequency, and sends the temperature data every minute goes to sle…

very nice tnx :sunglasses: * immediate searching in my junkbox but no thermistor to be found and a ‘normal’ tempsensor will never fit in memory I think [x560]

Hi, are you using the attiny internal thermometer? @Dennizr has added onto the miniaturized LMIC - originally for attiny by @rharte - would be interesting to see if that still works on the attiny! Would be my dream come true. The library is here: https://github.com/Kaasfabriek/Junior_Internet_of_…

The sensor has an external thermistor on the ADC2 (PB4) input channel. For channel switching simply add this switch statement in the RFM_Send_Package() function // change the channel of the RFM module switch (TCNT0 % 3) { case 0x00: //Channel 0 868.100 MHz / 61.035 Hz = 14222987 = 0xD9068B …

And if you would like to use a semi-random key to select the channel, just take a byte from the encrypted payload (or a byte from the MIC) and mask-out the 3 least significant bits as a pointer to the channel

@BoRRoZ , it will probably fit in memory easy but the question is if you have I/O available :slight_smile:

mmmmmmm… indeed :slight_smile: a while back I bought a handfull of these boards for almost nothing… never used them. reading this topic I installed the digispark driver and got blink to work :slight_smile: https://diyprojects.io/tutorial-program-cjmcu-attiny85-lilytiny-lilypad/ [comp]

I made some Ampere Tests today with the node alone sending two dummy bytes every minute. During sleep the amperage was 0,24mA. [DSC_1245] With the thermistor connected, the current strength is slightly higher 0.39 mA due to the 10K resistor. I do not know if I can bring it much lower. All tips ar…

I think I found the solution with disabling the ADC ADCSRA &= ~(1<<ADEN); in sleep mode saves about 235uA. without sensor 5uA in sleep mode I am happy :yum: And with the thermistor connected 153uA. [ttn]

which bootloader do you use ? will it work with v2.0 ? why the bod @ 1v8 ?

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ATtiny85 + RFM95 Temperature Sensor

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IoT_Marco December 17, 2017, 8:52pm 6

Very nice, I have a few ATtiny’s and give it a try. Thanks for sharing!

Looking for a ready to buy PCB for a Lora node with an ATtiny85