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Problem with serial monitor and Baby Orangutan

I got the Baby Orangutan and the AVR USB programmer v1 and I’ve been testing it for 4 whole days and solving all the problems I had with these.
I am trying to display on the serial monitor some text and I can’t get it to work. I’m using the Arduino IDE with the correct port and everything because I already tested the LED blink before.
For the serial monitor I connected the RX and TX pins from the AVR USB programmer v1 to the PD0 and PD1 of the Baby Orangutan respectively and the GROUND pin to the Baby Orangutan’s ground pin. Then I have the Baby Orangutan powered with a 9V.
The code is this:

void setup(){

void loop(){

The programming port is the COM6 and after uploading the code to the Orangutan, I change the port to COM5 for the serial monitor and when I click it with the rate of 9600, nothing appears in the serial monitor.
Everytime I send text through the serial monitor, the green LED from the AVR USB programmer v1 blinks for a second.
Also when I upload this code, the red LED of the Baby Orangutan stays HIGH. I tested it and when the code has Serial.begin(9600) in the setup, its when this red LED stays HIGH.
When I unplug the 9V battery from the Baby Orangutan, the board still has its LEDs (red and green) ON and its when I pull the TX when everything turns OFF.
I also tried to set the PD0 pin to be the INPUT and PD1 to be the OUTPUT in the setup but won’t work either.

There is something I’m missing and I don’t know why. I need help.

Thank you,


Well, today after more research I found that I have to connect the RX pin from the AVR USB Programmer to the TX pin (something that doesn’t seem logical :rofl: ) from the Baby Orangutan and vice versa with the other pin.

Keeping this here so if someone has the same problem he will be able to solve it.


1 Like

Yes, Tx pin from Programmer goes to Rx pin on Orangutan and vice versa. Each device transmits on its Tx pin and receives on its Rx pin so they have to be connected this way to communicate data to each other.
I too noticed that as soon as the Serial.begin command is run then the red led lights up and stays that way, so I guess it’s normal behaviour as the led pin is also used as the serial Tx pin. Not too convenient as it means you can’t use the led when serial comms is active.