The SCT detector interfaces with the ATLAS Level 1 using the LHC-wide TTC (Timing, Trigger, and Control) system. The design of the TIM ( TTC Interface Module), part of the SCT off-detector electronics [ 1 ], and the interface with the RODs ( Read Out Drivers), is described. Also described is the forerunner of the TIM, the CLOAC ( Clock And Control) MASTER module, developed to provide a stand-alone timing and trigger capability in the absence of the TTC system. CLOACs are currently used in the SCT tests at CERN. They are also available to the SCT community for use in front-end modules testing.