sola - 2021-11-30

Hello, I made an I/O expander device for the Raspberry PI based on the MCP23S17. I decided to edit the driver for it to delete some options I don't need and to add an IO mapping to the device.

I managed to delete the things I don't need but I do not understand how to add the I/O mapping to variables. I have added them in the HostParameterSet in the xml file and they do appear in when I add the device to a project. But how do I assign a value to it?
For example if I have 8 outputs on my device, I would like to pass a single byte to a variable to set the states of the outputs.
This works:
IOEXP_IO.byOutputs := 2#10101010;

But I want to be able to do this:
out AT %QB4: BYTE;

out:=2#10101010;

I know I am a noob but it is pretty difficult to find any documentation about this and what exists is difficult to understand for someone who is new to this like me. This is for my thesis project.

I have attached my driver, xml and testing project.