CN8478 Datasheet, PDF (218/221 Pages) Conexant Systems, Inc – Multichannel Synchronous Communications Controller (MUSYCC)

Appendix A JTAG Interface
A.2 BYPASS Register
CN8478/CN8474A/CN8472A/CN8471A
Multichannel Synchronous Communications Controller (MUSYCC™)
A.2 BYPASS Register
The BYPASS register is a 1-bit shift register that passes TDI data to TDO, which
facilitates testing other devices in the scan path without having to shift the data
patterns through the compare Boundary Scan register of the CN8478.
Table A-2. JTAG Timing Table
Label
Description
t_per
Period, TCK
t_pwl
Pulse Width Low, TCK
t_pwh
Pulse Width High, TCK
t_rec
Recovery, the rising edge of TCK from the rising edge of TRST~
t_s
Setup, TMS, TDI to the rising edge of TCK
t_h
Hold, TMS, TDI from the rising edge of TCK
t_en
Enable, TDO from the falling edge of TCK
t_pd
Propagation Delay, TDO from the falling edge of TCK
t_dis1
Disable, TDO from the falling edge of TCK
t_dis2
Disable, TDO from the falling edge of TRST~
Min
—
0.4 t_per
0.4 t_per
100
15
15
—
—
—
—
Max
Unit
100
ns
0.6 t_per
ns
0.6 t_per
ns
—
ns
—
ns
—
ns
15
ns
15
ns
15
ns
100
ns
A-2
Conexant
100660E