I have now been able to get the LCD Char Sender to work after some debugging.

The system is told where in memory it can extract text from and then provides the control signals to the display.

Note that it can be anywhere in memory and does not need to be word aligned so if I create some text in a program I just send the address of the start of the text and off it goes. As the system can also be set so that it keeps reading from the system 19 times a second I can have a low level of 'animation'.

Also note that it sets the cursor to the bottom line after writing 16 characters and then writes a further 16 characters. The cursor is then sent to the top line again.
The infrastructure is non blocking so I can have the processor running and the LCD Character sender running in the background. It's only if the text is sitting in the same memory block will there be contention and that is arbitrated.