Hierarchical system test by an IEEE 1149.5 MTM-bus slave-moduleinterface core

摘要

An IEEE 1149.5 module test and maintenance (MTM) bus slave moduleninterface core is presented, which is used for direct access from thensystem bus to the IEEE 1149.1 chip-level or on-chip buses to facilitatenhierarchical system test and diagnosis. The hierarchical testnmethodology also is presented, which is applicable to the system-on-chipnenvironment, All the standard 1149.1 instructions, such asnSAMPLE/PRELOAD, EXTEST, BYPASS, and even RUNBIST, can be performednwithin three 1149.5 read/write-data message cycles. The messages arentransmitted between the MTM-bus master module (Ill-module) and the slavenmodule (S-module). We adopt the full test access port control method tonactivate the 1149.1 boundary-scan paths via the 1149.5 MTM-bus. OurnS-module interface circuit implements 16 CORE commands and onenread/write-data command. It has been prototyped using anfield-programmable gate array chip and implemented by a full-customnchip. Hierarchical test of multiple 1149.1 compatible boards has beennexperimentally verified