[dhy5202003]

求助：simulink仿真Input port 1 of 'untitled/To Workspace' is not connected.
I
simulink仿真时，命令窗口出现一下错误提示，
nput port 1 of 'untitled/To Workspace' is not connected.
simulink弹窗一下提示
Unable to determine signal dimensions. There is a loop consisting of 'untitled/MATLAB Fcn1' that cannot be resolved because signal dimensions are defined by a cyclic relationship. Specifying the signal dimensions on Inport, Mux, Selector, Demuxes will help resolve signal dimensions in the loop. You can also use the Signal Specifications to define the signal dimensions

请问高手如何解决，谢谢，