Cypress CY7C1380D Computer Hardware User Manual


 
CY7C1380D, CY7C1382D
CY7C1380F, CY7C1382F
Document #: 38-05543 Rev. *F Page 14 of 34
when the EXTEST is entered as the current instruction. When
HIGH, it enables the output buffers to drive the output bus. When
LOW, this bit places the output bus into a High-Z condition.
This bit can be set by entering the SAMPLE/PRELOAD or
EXTEST command, and then shifting the desired bit into that cell,
during the Shift-DR state. During Update-DR, the value loaded
into that shift-register cell latches into the preload register. When
the EXTEST instruction is entered, this bit directly controls the
output Q-bus pins. Note that this bit is preset HIGH to enable the
output when the device is powered up, and also when the TAP
controller is in the Test-Logic-Reset state.
Reserved
These instructions are not implemented but are reserved for
future use. Do not use these instructions.
TAP Timing
TAP AC Switching Characteristics Over the Operating Range
[10, 11]
Parameter Description Min Max Unit
Clock
t
TCYC
TCK Clock Cycle Time 50 ns
t
TF
TCK Clock Frequency 20 MHz
t
TH
TCK Clock HIGH time 20 ns
t
TL
TCK Clock LOW time 20 ns
Output Times
t
TDOV
TCK Clock LOW to TDO Valid 10 ns
t
TDOX
TCK Clock LOW to TDO Invalid 0 ns
Setup Times
t
TMSS
TMS Setup to TCK Clock Rise 5 ns
t
TDIS
TDI Setup to TCK Clock Rise 5 ns
t
CS
Capture Setup to TCK Rise 5 ns
Hold Times
t
TMSH
TMS Hold after TCK Clock Rise 5 ns
t
TDIH
TDI Hold after Clock Rise 5 ns
t
CH
Capture Hold after Clock Rise 5 ns
t
TL
Test Clock
(TCK)
Test Mode Select
(TMS)
t
TH
Test Data-Out
(TDO)
t
CYC
Test Data-In
(TDI)
t
TMSH
t
TMSS
t
TDIH
t
TDIS
t
TDOX
t
TDOV
DON’T CARE UNDEFINED
Notes
10.t
CS
and t
CH
refer to the setup and hold time requirements of latching data from the boundary scan register.
11. Test conditions are specified using the load in TAP AC test conditions. t
R
/t
F
= 1ns.
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