The /R startup switch assigns the computer's Register Number. It is recommended that each computer on a network have a unique Register Number.
Register Number supports values between 1 and 9999. It is recommended to use Register Numbers below 41 because the Closeout Module supports starting drawer amounts for only Register Numbers 1 through 40.
/R# - where # can be any integer between 1 and 9999.
Example: Keystroke.exe /R3
See: INIFILE setting Register=