ADSP-21060 Analog Devices, ADSP-21060 Datasheet - Page 12

• Manufacturer Part Number: ADSP-21060
• Description: ADSP-2106x SHARC DSP Microcomputer Family
• Manufacturer: Analog Devices

Connecting CLKIN to Pin 4 of the EZ-ICE header is optional.
The emulator only uses CLKIN when directed to perform
operations such as starting, stopping and single-stepping mul-
tiple ADSP-21061 in a synchronous manner. If you do not need
these operations to occur synchronously on the multiple proces-
sors, simply tie Pin 4 of the EZ-ICE header to ground.
If synchronous multiprocessor operations are needed and
CLKIN is connected, clock skew between the multiple ADSP-
21061/ADSP-21061L processors and the CLKIN pin on the
EZ-ICE header must be minimal. If the skew is too large, syn-
chronous operations may be off by one or more cycles between
processors. For synchronous multiprocessor operation TCK,
ADSP-21060/ADSP-21060L
CLKIN
TRST
EMU
TMS
TCK
TDO
TDI
*
*
*
OPEN DRAIN DRIVER OR EQUIVALENT, i.e.,
5k
5k
TDI
TDI
TDO
TDO
TDI
TDI
TMS, CLKIN and EMU should be treated as critical signals in
terms of skew, and should be laid out as short as possible on
your board. If TCK, TMS and CLKIN are driving a large num-
ber of ADSP-21061 (more than eight) in your system, then
treat them as a clock tree using multiple drivers to minimize
skew. (See Figure 7, JTAG Clock Tree, and Clock Distribution
in the High Frequency Design Considerations section of the
ADSP-2106x User’s Manual, Second Edition.)
If synchronous multiprocessor operations are not needed (i.e.,
CLKIN is not connected), just use appropriate parallel termina-
tion on TCK and TMS. TDI, TDO, EMU and TRST are not
critical signals in terms of skew.
For complete information on the SHARC EZ-ICE, see the ADSP-
2100 Family JTAG EZ-ICE User’s Guide and Reference.
TDO
TDO
TDI
TDI
EMU
TDO
TDO
SYSTEM
CLKIN