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(VCC) Presence detect. Indicates that the emulation
cable is connected and that the target is
powered up. PD should be tied to VCC in the
target system.
IO
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.
OI
TCK_RET Test clock return. Test clock input to the emu-
lator. May be a buffered or unbuffered version
of TCK.
IO
TDI Test data input O I
TDO Test data output I O
TMS Test mode select O I
TRSTTest 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.)