Texas Instruments TMS320C6201 Reference Manual page 443

Connections Between the Emulator and the Target System
Buffered transmission signals. In this situation, the distance between
the emulation header and the processor is greater than six inches. Emula-
tion signals TMS, TDI, TDO, and TCK_RET are buffered through the same
package.
JTAG Device
EMU0
EMU1
TRST
TMS
TDI
TDO
TCK
J
The EMU0 and EMU1 signals must have pullup resistors connected to
to provide a signal rise time of less than 10 µs. A 4.7-kΩ resistor is
V
CC
suggested for most applications.
J
The input buffers for TMS and TDI should have pullup resistors con-
nected to V to hold these signals at a known value when the emula-
CC
tor is not connected. A resistor value of 4.7 kΩ or greater is suggested.
J
To have high-quality signals (especially the processor TCK and the
emulator TCK_RET signals), you may have to employ special care
when routing the PWB trace. You also may have to use termination
resistors 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.
J
Since TRST is an asynchronous signal, it should be buffered as
needed to insure sufficient current to all target devices.
Greater Than
6 Inches
V CC
Emulator Header
13
EMU0
14
EMU1
2
TRST
1
TMS
3
TDI
7
TDO
11
TCK
9
TCK_RET
Designing for JTAG Emulation
V CC
5
PD
4
GND
6
GND
8
GND
10
GND
12
GND
GND
15-9