sorg:
I've changed the Display pins 13 as 12 to 10 and 9 and now this part of my project works!
For the future be aware that Pin 10 on an Uno also has special significance for SPI. It does not have to be used as part of the SPI process but it must be set as OUTPUT if the Uno is to act as an SPI master.
Using Pin 10 to write data to the display is fine.
...R