Power-on self-test method and device for I/O plug-in

The invention discloses a power-on self-test method and device for an I/O plug-in. The power-on self-test method and device for the I/O plug-in are used for performing systematic and complete self-test on the plug-in and preventing the plug-in with hidden dangers from causing fault when a system is in operation. According to the technical scheme, the method comprises the steps of performing self-test of an SRAM chip, performing self-test of a flash memory chip, performing self-test of an RAM in a CPU chip, performing self-test of a communication channel in the plug-in and performing power-on self-test of the plug-in channel.