LPC 1769 Using SSP SSEL as GPIO

Discussion created by lpcware Employee on Jun 15, 2016
Content originally posted in LPCWare by Scavmaster on Wed Aug 20 08:40:13 MST 2014

I am using LPC1769 SSP1 for SPI communitcation on a AOA Kit Dev. Board.

For now I am only using one sensor which is why I am using the provided SSEL1 and it works just fine.

Due to the project I am working on I need to keep expandability in mind, so I would like to have two SSEL signals in future.
I was thinking about using the provided SSEL1 for as long as possible as it is working right now and then use a second GPIO pin for the second slave select I will generate in future. Therefore of course I need to disable the provided SSEL1 function and use the same pin as GPIO so I can have my own slave selection working, right?

The data sheet says P0.6 can be used for four functions one of which is GPIO and another SSEL1. Nothing mentioned about a forced function in case of using SSP as far as I can tell.

Still I am struggeling using SSEL1 as GPIO. As soon as I am using SSP module, P0.6 works as SSEL1.
I checked my hardware initialization for a couple of times and I am almost certain I am not initializing that pin as SSEL1 but as GPIO.

Am I getting something wrong here? Am I doing something wrong here? Can I use SSEL1 as GPIO whilst using SSP1?

Thanks a lot!