NEC mPD98410 User Manual page 182

JCK pin signal
JMS pin signal
Controller state
JDI pin signal
Input data to IR
IR shift register
Parallel output of IR
Note
Input data to TDR
TDR shift register
Parallel output of TDR
Selected register
JDO enable signal
JDO pin signal
Note TDR (Test Data Register): Boundary scan register and bypass register
Remark : Don't care or undefined
182
CHAPTER 5 JTAG BOUNDARY SCAN
Figure 5-4. Operation of Test Logic (instruction scan)
Bypass
Inactive Active
Instruction register
Inactive Active
New instruction
Old data
Inactive