Magsense :Rsv PIN,The project contains 5 buttson that must hav a rsv

[Frank_vec]

When the project has 4 buttons，There is no Rsv pin;but 5 buttons,there is;

The project contains 5buttons,How does this Rsv pin connect in PCB  ?

Thanks

Magsense  当使用4个buttons的时候没有RSV pin脚，我现在用5个buttons，这个RSV 在PCB 上怎么接呢？

[Hari · Accepted solution]

Hi @Frank_vec 

The MagSense sensing algorithm requires one additional Lx GPIO per port for successful scanning. In case you have more than one sensor in a port, then the algorithm will reuse the pins from inactive sensors (sensors that are not scanned at that time instance) for its operation. In your case, Button4 has its Lx pins assigned to Port 3. Since there are no other sensors having Lx in port 3, we require one additional GPIO which is indicated by the Rsvd pin. In case you add another sensor, say Button5, and assign its Lx to Port 3, then you will no longer require this Rsvd pin. 

Best regards, 
Hari

[Frank_vec]

as the pdf  show: The rsv is internal use, In PCB   the rsv need not connected to others? in the othe side ,Coudl I use RSV in code ?

Thanks 

[Hari]

Hi @Frank_vec 

The RSV pin need not be connected to anything in the PCB. Please treat that pin as a NC pin. It is recommended not to use that GPIO for any purpose in code either. In case you are using, please make sure that it is free and configured in analog mode when the MagSense scan is active. 

Best regards, 
Hari

[Frank_vec]

Hi @Hari 

very useful，thanks for your help ，very 谢谢