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TMS320C6670 Peripheral Information and Electrical Specifications
Copyright 2012 Texas Instruments Incorporated
SPRS689D—March 2012
Multicore Fixed and Floating-Point System-on-Chip
TMS320C6670
7.34.3.1 IEEE 1149.1 JTAG Compatibility Statement
For maximum reliability, the C6670 DSP includes an internal pulldown (IPD) on the TRST pin to ensure that TRST
will always be asserted upon power up and the DSP's internal emulation logic will always be properly initialized
when this pin is not routed out. JTAG controllers from Texas Instruments actively drive TRST high. However, some
third-party JTAG controllers may not drive TRST high but expect the use of an external pullup resistor on TRST.
When using this type of JTAG controller, assert TRST to initialize the DSP after powerup and externally drive TRST
high before attempting any emulation or boundary scan operations.
7.34.3.2 JTAG Electrical Data/Timing
Figure 7-60
JTAG Test-Port Timing
Table 7-86
JTAG Test Port Timing Requirements
(see
No.
Min
Max
Unit
1
t
c(TCK)
Cycle time, TCK
34
ns
1a
tw(TCKH)
Pulse duration, TCK high (40% of tc)
13.6
ns
1b
tw(TCKL)
Pulse duration, TCK low (40% of tc)
13.6
ns
3
tsu(TDI-TCK)
Input setup time, TDI valid to TCK high
3.4
ns
3
tsu(TMS-TCK)
Input setup time, TMS valid to TCK high
3.4
ns
4
th(TCK-TDI)
Input hold time, TDI valid from TCK high
17
ns
4
th(TCK-TMS)
Input hold time, TMS valid from TCK high
17
ns
End of Table 7-86
Table 7-87
JTAG Test Port Switching Characteristics
(see
No.
Parameter
Min
Max
Unit
2
t
d(TCKL-TDOV)
Delay time, TCK low to TDO valid
13.6
ns
End of Table 7-87
TD
I
/ TMS
1a
1
3
TCK
4
TD
O
1b
2
Содержание TMS320C6670
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