Texas Instruments TMDSEMU560V2STM-U - Blackhawk XDS560v2 System Trace USB Emulator TMDSEMU560V2STM-U TMDSEMU560V2STM-U 데이터 시트
제품 코드
TMDSEMU560V2STM-U
Connections Between the Emulator and the Target System
3-13
Target Design Considerations for Using the XDS560 Emulation Pod
Importance of Good Design Practices
The target board designer should use good design practices to
minimize signal crosstalk and signal skew. The designer must also
take into account any propagation delays of these signals and the
effect that they will have on the timing of the emulation.
minimize signal crosstalk and signal skew. The designer must also
take into account any propagation delays of these signals and the
effect that they will have on the timing of the emulation.
Figure 3−5. Buffered Signal Connections
EMU0
EMU1
EMU1
TRST
TMS
TDI
TDO
TCK
TCK_RET
TVD
GND
GND
GND
GND
GND
GND
GND
GND
GND
13
14
14
1
2
9
11
7
3
Emulation header
VCC I/O
VCC I/O
EMU0
EMU1
TRST
TMS
TDI
TDO
TCK
EMU1
TRST
TMS
TDI
TDO
TCK
Target device
Greater than 6 inches
5
4
6
8
6
8
10
12
12
-
The EMU0 and EMU1 signals must have pullup resistors connected to
V
V
CC
to provide a signal rise time of less than 10
µ
s. A 4.7-k
Ω
resistor is sug-
gested for most applications.
-
The input buffers for TMS and TDI should have pull-up resistors con-
nected to V
nected to V
CC
to hold these signals at a known value when the emulator
is not connected. A resistor value of 4.7 k
Ω
or greater is suggested.
-
To have high-quality signals (especially the processor TCK and the emula-
tor TCK_RET signals), you may have to employ special care when routing
the PWB trace. You also may have to use termination scheme, which is
appropriate for your design to match the trace impedance. The emulator
pod provides optional internal parallel terminators on the TCK_RET and
TDO. TMS and TDI provide fixed series termination.
tor TCK_RET signals), you may have to employ special care when routing
the PWB trace. You also may have to use termination scheme, which is
appropriate for your design to match the trace impedance. The emulator
pod provides optional internal parallel terminators on the TCK_RET and
TDO. TMS and TDI provide fixed series termination.
-
Since TRST is an asynchronous signal, it should be buffered as needed
to insure sufficient current to all target devices.
to insure sufficient current to all target devices.
-
Additional considerations should be taken into account when designing a
target board. Such considerations include signal loading of vias and the
like.
target board. Such considerations include signal loading of vias and the
like.