# How to build new DTB

Source: https://forum.modalai.com/topic/923/how-to-build-new-dtb
Category: Flight Core and Legacy VOXL (https://forum.modalai.com/category/9/flight-core-and-legacy-voxl)
Tags: voxl-flight
Posted: 2022-05-09 20:15:53 UTC by jrestifo
Replies: 1 · Views: 426

## jrestifo · 2022-05-09 20:15:53 UTC

I want to be able to use a different CS pin for SPI9. For instance, if I wanted to make GPIO26 the CS for SPI9 instead. I see the DTS files in kernel/msm-3.18/arch/arm/boot/dts/qcom/msmcobalt-pinctrl.dtsi and others. How do I replace just the DTB on a VOXL unit? Or do I need to rebuild the whole kernel and replace the kernel as a whole?

## Reply by modaltb (ModalAI staff) · 2022-06-01 15:19:10 UTC

Hi @jrestifo ,

Super late on this response.  In general yes a kernel rebuild is needed.  There's some gotchas so if you are proceeding down this path let us know.