Unison Serial Access Protocol (USAP) operates differently depending on the version of EAC operating code installed in your Unison architectural processor.
Unison operating code 1.5 through 1.9.0
For systems utilizing Unison EAC operating code 1.5 through 1.9.0 with an architectural processor (CME, CMEd, or CMEi):
- USAP is a communication protocol that allows a device capable of outputting RS-232 protocol to interface with a Unison Lighting Control System. USAP is a “polled” system, meaning that Unison accepts commands from a transmitter and provides status only when queried.
An example of standard USAP functionality may include:
- Preset 1 is played from your Unison control station. To determine if Preset 1 has been played, the serial device must query the Unison processor to obtain the preset status.
Unison operating code 1.9.1 and later
For systems utilizing Unison EAC operating code 1.9.1 and later with an architectural processor (CME, CMEd, CMEi):
- Standard USAP is enhanced to include dynamic event based serial commands and responses. Serial command and response messages are sent from the Unison architectural processor to a connected RS-232 device when status of configured objects change. Standard event messages such as record, activate, deactivate, and macro execute are output from the Unison processor to the third party serial device without the need of additional status queries from the RS-232 device.
An example of bi-directional USAP functionality may include:
- Preset 1 is played from your Unison control station. The Unison processor sends a message to the serial device advising that preset 1 has been played.
CAUTION: USAP is a non-guaranteed protocol relying on best effort delivery of serial data. Excessive run lengths, high data transmission rates (baud rates), or poorly terminated wire may result in frequent data loss.
Unison Serial Access Protocol will allow you to perform the following functions in a Unison system: