But we do appreciate the clean and orderly technique that [Eric Rogers] uses to add multiple SPI SRAM chips to an Arduino. The heavy lifting is done with a CPLD shield called the Amani 64.

Run in the Arduino IDE the HelloWorld example with an ili9488 in SPI. In fact, you don't need an ili display to try this, because it fails at compile time. The possible wiring errors, are irrelevant ...

To prevent data corruption when using multiple SPI devices on the same bus, care must be taken to ensure that they are only accessed from within the main loop, or from the interrupt routine, never … ...