© 2002 QuickLogic Corporation

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QL4016 QuickRAM Data Sheet Rev I

The 1149.1 JTAG standard requires the following three tests:

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places a device into an external boundary test mode, selecting the boundary scan

register to be connected between the TAP's Test Data In (TDI) and Test Data Out (TDO)

pins. Boundary scan cells are preloaded with test patterns (via the Sample/Preload

Instruction), and input boundary cells capture the input data for analysis.

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functional mode, while selecting the boundary scan register to be connected between

the TDI and TDO pins. For this test, the boundary scan register can be accessed via a

data scan operation, allowing users to sample the functional data entering and leaving

the device.

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scan entirely, so the data passes through the bypass register. The Bypass instruction

allows users to test a device without passing through other devices. The bypass register

connects the TDI and TDO pins, allowing serial data to be transferred through a device

without affecting the operation of the device.