Better SPI Bus design in 3 steps

Paul over at Dorkbotpdx has written an article on 3 steps to good SPI Bus design:

A much better SPI bus design can prevent conflicts. 3 simple improvements are needed:

1. Use pullup resistors on all chip select signals.
2. Verify tri-state behavior on MISO: use a tri-state buffer chip if necessary.
3. Protect bus access with SPI.beginTransaction(settings) and SPI.endTransaction().