A control apparatus which is inexpensive and highly effective in shortening a start-up time, a method of controlling the control apparatus, and a digital broadcast receiving apparatus are provided. The control apparatus includes: a control microcomputer; at least one device; and a ROM which stores a simple control program, a main body program, and a boot loader. The simple control program includes an interrupt program having an interrupt for starting the at least one device so that the at least one device is activated, accepts an interrupt signal requesting for the interrupt from the at least one device during loading of the main body program, and performs the interrupt.