Designing Your Target System’s Emulator Connector (14-Pin Header)
E-3
Design Considerations for Using XDS510 Emulator
Table E–1. 14-Pin Header Signal Descriptions
Signal
Description
Emulator
†
State
Target
†
State
EMU0
Emulation pin 0
I
I/O
EMU1
Emulation pin 1
I
I/O
GND
Ground
PD(V
CC
)
Presence detect. Indicates that the emulation
cable is connected and that the target is
powered up. PD should be tied to V
CC
in the
target system.
I
O
TCK
Test clock. TCK is a 10.368-MHz clock
source from the emulation cable pod. This
signal can be used to drive the system test
clock.
O
I
TCK_RET
Test clock return. Test clock input to the emu-
lator. May be a buffered or unbuffered version
of TCK.
I
O
TDI
Test data input
O
I
TDO
Test data output
I
O
TMS
Test mode select
O
I
TRST
‡
Test reset
O
I
† I = input; O = output
‡ Do not use pullup resistors on TRST: it has an internal pulldown device. In a low-noise
environment, TRST can be left floating. In a high-noise environment, an additional pulldown
resistor may be needed. (The size of this resistor should be based on electrical current
considerations.)
