Can't read AVR PINx port value?

Question

Electronics

It doesn't work out, everything has tried all the ways and Hi-Z.
Testing in Proteus. Here is the simplest code:
start:
ldi r16, pinb
rjmp start
In the proteus, register r16 is always 16hex. If you read other ports, then the values ​​\u200b\u200bare slightly different from port B. Even if a voltage of 5 Volts is applied to the outputs, it is still the same value of 16hex.

Answer 1

Instead of LDI, you need to use the IN instruction. And for output to the register, respectively, OUT.

Answer 2

The LDI R, N instruction loads the 8-bit value of N into register R.

Answer 3

Well, the pinb register is also 8-bit. Why is the wrong value loaded into the register when using LDI ?