Patent ID: 7334738

Claim:
A riser card identification system for identifying a riser card electrically connected with a computer system having a Basic Input Output System (BIOS) and a storage unit, the riser card identification system comprising: a setting unit for allowing users to set an identification mark for at least one riser card and duty cycle of a pulse signal corresponding to the identification mark, and for saving the identification mark and the corresponding duty cycle to the storage unit of the computer system; a signal generating unit for generating a variety of waveform signals with different duty cycles according to a control signal output by the computer system; a charging/discharging unit built inside the riser card for receiving the waveform signals and performing a charging/discharging process on the received waveform signals, so as to generate analog signals, the charging/discharging unit having a characteristic value as the identification mark of the riser card corresponding to the charging/discharging unit; a signal comparing unit for comparing the analog signals output from the charging/discharging unit with a reference signal output by the computer system, and generating a digital signal according to the comparison between the analog signals and the reference signal; and a signal reading unit for reading duty cycle of the digital signal output from the signal comparing unit such that the BIOS of the computer system identifies the riser card being electrically connected with the computer system according to the read duty cycle and information stored in the storage unit.