SPRZ200E
TMS320VC5509A Silicon Errata
27
Emulation Prone to Failure Under Certain Situations (Continued)
0
4
2
1
3
0 5
10
15
−1
20
V
olts (V)
nanoseconds (ns)
2.5 V
0.6 V
Figure 3. Bad TCK Transition
V
olts (V)
nanoseconds (ns)
0
2
1
3
0 5 10
15
−1
20
4
2.5 V
0.6 V
Figure 4. Good TCK Transition
Workaround:
As the problem may be caused by one or more of the above factors, one or more of the steps
outlined below may be necessary to fix it:
•
Avoid using a socket
•
Ensure the board design achieves rise times and fall times of less than 3 ns with clean
monotonic edges for the TCK signal.
•
For designs where TCK is supplied by the emulation pod, use a C55x Emulation
Adapter Board, part number DSP8102U. To order a C55x Emulation Adapter Board,
please contact the TI Product Information Center (PIC).
