Received my two Monteinos yesterday! I am new to Arduino -
First question -
My DHT11 works great on pin 4 as INPUT_PULLUP but not on pin 2. It happens to both Moteinos I received. I have the following connection
DHT11 + -> 3.3V
DHT11 - -> GND
DHT11 middle pin -> pin 2 (software set it to use INPUT_PULLUP).
Second question -
I only purchased a single FTDI adapter. Can I power the 2nd Moteino with the 1st one (which is powered by the FTDI adapter)? Shall I do
M1 3.3->M2 VIN
M1 GND->M2 GND
Third question -
One of my sensors needs 5V input, do I need a separate power source for it? Can moteino output 5V in any of its pins?
Fourth question -
I am using macbook air. I have to unplug and replug the usb cable each time I want to write the firmware. If I don't do that I get the following error
avrdude: stk500_getsync(): not in sync: resp=0x00
The fourth problem is solved by installing the FTDI driver
Question 2 is solved.
the following configuration worked! My guess is that M1 VIN outputs 5V
M1 is powered by usb
M1 GND <--> M2 GND
M1 VIN <--> M2 VIN
Pin 2 is used by the transceiver. Please check the pinout diagrams at moteino.com to see what is available and what taken depending on what options you have installed on your Moteino.
Since Moteinos run at 3.3V they cannot output 5V on any of the pins. You can supply a 5V source to the VIN and then also use that to power your 5V peripheral. Or you can get a Power Shield (when it's back in stock) and use that to boost to 5V.
Makes sense. Thank you!