1) метод сквозного сдвигового регистра с опросом состояний элементов (алгоритм диагностики) 2) диагностическая система с последовательным сканированием
(circuit design) (LSSD) A kind of scan design which uses separate system and scan clocks to distinguish between normal and test mode. Latches are used in pairs, each has a normal data input, data output and clock for system operation. For test operation, the two latches form a master/slave pair with one scan input, one scan output and non-overlapping scan clocks A and B which are held low during system operation but cause the scan data to be latched when pulsed high during scan. In a single latch LSSD configuration, the second latch is used only for scan operation. Allowing it to be use as a second system latch reduces the silicon overhead.