This invention relates to the field of internal circuit testing technology for airborne equipment, specifically a
boundary scan-based testing method for 659
bus input boards. The method includes: Step 1, designing the 659
bus main control board and test resource boards, designing the timing and
control logic, and the industrial computer test control program; Step 2, connecting the 659
bus main control board, test resource boards,
boundary scan controller, and industrial computer, and connecting the 659 bus main control board, test resource boards, and
boundary scan controller to the board under test; Step 3, performing 659 bus testing; Step 4, performing input acquisition testing, including AD conversion testing and discrete input testing; Step 5, performing self-test functionality testing. This invention enables rapid fault location of 659 bus input boards, significantly reducing waste in the production process, saving resources, and lowering costs; it also features a simple structure, reliable operation, and strong applicability; and improves the testing and maintenance capabilities of airborne products.