SCANPSC110F

SCANPSC110F SCAN Bridge Hierarchical and Multidrop Addressable JTAG Port (IEEE1149.1 System Test Support) March 1993 Revised August 2000 SCANPSC110F SCAN Bridge Hierarchical and Multidrop Addressable JTAG Port (IEEE1149.1 System Test Support) General Description The SCANPSC110F Bridge extends the IEEE Std. 1149.1 test bus into a multidrop test bus environment. The advantage of a hierarchical approach over a single serial scan chain is improved test throughput and the ability to remove a board from the system and retain test access to the remaining modules. Each SCANPSC110F Bridge supports up to 3 local scan rings which can be accessed individually or combined serially. Addressing is accomplished by loading the instruction register with a value matching that of the Slot inputs. Backplane and inter-board testing can easily be accomplished by parking the local TAP Controllers in one of the stable TAP Controller states via a Park instruction. The 32-bit TCK counter enables built in self test operations to be performed on one port while other scan chains are simultaneously tested. Features s True IEEE1149.1 hierarchical and multidrop addressable capability s The 6 slot inputs support up to 59 unique addresses, a Broadcast Address, and 4 Multi-cast Group Addresses s 3 IEEE 1149.1-compatible configurable local scan ports s Mode Register allows local TAPs to be bypassed, selected for insertion into the scan chain individually, or serially in groups of two or three s 32-bit TCK cou...