Switch apparatus switching between basic input output system chip and diagnostic card

A switch apparatus, comprising:

• a first connector arranged on a motherboard;
• a platform controller hub (PCH) chip arranged on the motherboard and coupled to the first connector through a low pin count (LPC) bus, the PCH chip comprising a first trapping pin and a second trapping pin;
• a first basic input output system (BIOS) chip arranged on the motherboard, and coupled to the PCH chip through a serial peripheral interface (SPI) bus;
• a switch circuit arranged on the motherboard;
• and
• a diagnostic card, comprising:
• a second connector being detachably plugged into the first connector;
• and
• a second BIOS chip coupled to the second connector, to output a high level control signal through the second connector;
• wherein the switch circuit receives the high level control signal from the second BIOS chip through the first connector in response to the second connector being plugged into the first connector, the switch circuit outputs high level switch signals to the first and second trapping pins of the PCH chip, to select the second BIOS chip to bootstrap the motherboard;
• wherein the switch circuit does not receive the high level control signal in response to the second connector not being plugged into the first connector, the switch circuit outputs low level signals to the first and second trapping pins of the PCH chip, to select the first BIOS chip to bootstrap the motherboard.