Abstract: In this paper we are coming up with an embedded system with ARM7 processor controlling the operation of the elevator and camera. The microprocessor is programmed to run three tasks namely an elevator, a camera, and an embedded shell. The elevator and camera work together with the camera taking a snapshot of the occupants in the elevator every time the door opens. The tasks need precise timings which require employment of a real time operating system which provides determistic task switching’s and precise outputs. This paper employs RTX real-time operating system for the three tasks to run concurrently.

The elevator is programmed in a way to accept simultaneous pressing of the entire floor buttons and is based on a UART system which makes display to be connected to it. The camera takes a photo as soon as the door is opened as it is given as a separate task there is no way the camera will fail to take a photo before the door is closed.

This paper also includes an embedded shell which can monitor and manipulate any memory location on the target board making it a powerful tool for debugging errors and can read and write data on to various memory locations in the processor. It can be used on any embedded system using an ARM7 processor giving it a wide range of applications.

Keywords : Multitasking, Embedded Shell, ARM7 processor, RTX.