Brushless DC Motor Hall effect sensors, Calculate the position of rotor

Hello to all.
First of all sorry if my English is poor.
I have a Brushless dc motor and I want to calculate the speed of rotor and rotor position by 3 Hall effect sensors.
1-Which pins of MCU I should connect the output of Hall sensors. I mean which unit of MCU?
2-How can I find the position of rotor by that.I mean how to calculate?
My circuit is like below.

Very thanks.

Any digital input pins. These are hall-switches with a logic output, not analog sensors, note.

You read the pattern (6 possible patterns), tells you which 60-degree segment the motor is in.
You can't tell position any better without an encoder.

The sequence normally goes like:

001
011
010
110
100
101
001

or a reflected/rotated version equivalent to that.

Some motors have the sensors in a different arrangement (60 degrees spacing rather than 120 degrees)

001
011
111
110
100
000
001

Thanks.
You say I can't find the real speed of rotor by these 3 sensors, yeah?
How much error does it have?
The maximum speed of my motor is about 1500 rpm.
Very thank you.

Why not, you get a 6, 12, 18 or 24 commutation events per rotation for a 2,4,6,8-pole moter...