16. General device requirements
| Required |
17. PS/2 specifications by IBM and 8042 chip (or equivalent), if PS/2 used
| Required |
18. USB Specification and USB device class specification, if USB is used
| Required |
19. Wireless specifications, if wireless device is used
| Required |
20. PS/2- style keyboard returns expected scan codes
| Required |
21. No interference between keyboards for multiple devices
| Required |
22. Windows and Application Logo keys
| Recommended |