Reading GPIO input assembly

[GastonAznarez]

Hi, i'm a Computer science student. I'm trying to read the pin #4 of mi Raspberry Pi 3 B with assembly code but i can not make it work.
If someone can help me I will be grateful.
This is my code:

Code: Select all

.equ GPIO_GPLEV0, 0x34
.equ GPIO_4, 0x10	
.equ PERIPHERAL_BASE, 0x3F000000

mov w8, PERIPHERAL_BASE + GPIO_BASE    //0x3F200000
ldr w9, [x8, GPIO_GPLEV0]               //Get the 0-31 GPIO states
tbnz w9, #4,  jump //Branch if the 4th bit (0x10) is 1 who corresponds to the pin #4

[Paeryn]

That is gpio 23 not 4. Looks like you are confusing the wiringpi name/number (which looks to be labeled #4 on that pin) with the actual BCM gpio number which you need to use when reading the hardware registers.

[B.Goode]

I'm sure @Paeryn is correct.

You might find this interactive website that documents the Raspberry Pi header instructive: https://pinout.xyz/pinout/pin16_gpio23

[GastonAznarez]

I'm sure @Paeryn is correct.

You might find this interactive website that documents the Raspberry Pi header instructive: https://pinout.xyz/pinout/pin16_gpio23

That is gpio 23 not 4. Looks like you are confusing the wiringpi name/number (which looks to be labeled #4 on that pin) with the actual BCM gpio number which you need to use when reading the hardware registers.

Thank you very much to both. It is working now.