The invention concerns a combined surgical microscope system having a surgical microscope and a retinal diagnostic device of modified configuration having transscleral pulsed illumination. The portable electronic device includes a body, a cover, a button, a movable pin and a battery. The stored procedures may be written to a transaction log and a check made to verify that all of the stored procedures from which the business service is constructed have been written to the log. Further, the computing device may be configured to detect a construction zone sign in the image portions, and determine a type of the construction zone sign. The condition switch turns on and off based on engine conditions.