Serial on Attiny44 does not work as expected.

[Veteran-hd]

Attiny44,
the wire going to the Arduino RX is connected to AIN0.
AI0(ATTiny44) -> RX(arduino)
GND(ATTiny44) -> GND(arduino)
Code:

int w=1;

void setup() {
  Serial.begin(9600);
}

void loop() {
  Serial.print(w);
}

The port monitor displays squares.

The port monitor speed varies, from 2400 to 38600.
Firmware is set to 1, 2, 4, and 8 MHz.

I changed the speed from 2400 to 38600 in various combinations.
Squares, squares.
Where should I look for the problem?
Thanks!

[hmeijdam]

the wire going to the Arduino RX

Your serial receiver, that would be the first I would check.
Does it actually work, how you have it hooked up?

[Veteran-hd]

Does it actually work, how you have it hooked up?

Thanks for the clue!
I installed a different receiver and also changed the compilation parameters: 1 MHz, TX only, 4800 baud. Everything worked fine in these modes. Thanks!

[hmeijdam]

And if you want other than 1MHz, don't forget to do "burn bootloader". Even without a bootloader selected, "burn bootloader" is the command to actually change the system clock speed to what you have selected.