Abstract: Building and testing complex electronic products especially large scale computer systems are handled with control remaining with the owner of the design while a contract manufacturer does the basic manufacturing processes and testing. Nearly all levels of testing are accomplished without sharing high level descriptions of the end product or its features by providing only low level files for test functions. A tester used by the contract manufacturer to exercise the testing function for multiple circuit boards and that tester has numerous features that make it more useful and efficient. The tester has a computer system in it to run the tests using the low level files, and mimics the platform into which the boards will eventually become inserted. Various features provide additional ease of use and functionality.

Abstract: Electronics manufacturers, particularly ones building large scale computer systems, have a need to describe test vectors for third party manufacturers in a low level language description that does not reveal the circuit design to the third party but allows for the third party to build and test the systems, not just with static tests based on BSDL and netlist files, but dynamic tests as well. A conversion process for taking a high level language circuitry description and producing test vectors useable for translation into actual test vectors for testing board-level components of the large scale computer systems is described.

Abstract: Building and testing complex electronic products especially large scale computer systems are handled with control remaining with the owner of the design while a contract manufacturer does the basic manufacturing processes and testing. Nearly all levels of testing are accomplished without sharing high level descriptions of the end product or its features by providing only low level files for test functions. Testing is accomplished without sharing the high level code descriptive of the system design so confidential information is retained. Testing using the low level data is made sufficient to identify what parts need repair despite the lack of high-level information transfer.

Abstract: An apparatus for efficiently testing a plurality of memory devices at the board level. The logic for the present invention is minimal and can be placed on a controller chip within the board design. In addition, the interconnect lines between the controller chip and each of the plurality of memory devices can also be tested. Finally, the present invention requires minimal setup time and performs a functional test of the memories in a very short period of time.

Abstract: A method for comprehensively testing embedded RAM devices and a means for detecting if any of the cells within the embedded RAM devices have a slow write recovery time. The preferred mode of the present invention utilizes built-in self-test (BIST) techniques for testing the embedded RAM's within a VLSI device. In accordance with the present invention, a modified 5N march test sequence is performed on the embedded RAM devices. The modified 5N March test sequence is a simple algorithm implemented in programmable hardware that has the capability of ensuring that the embedded RAM devices are functional and that they meet the recovery time requirements. The preferred mode of the present invention uses this algorithm to determine if the embedded RAMs are operating properly before the VLSI devices are used in card assembly. However, this method can also be used after card assembly to monitor the embedded RAM's integrity.