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Desktop Transceiver SFX-TAP4_2/C, V0.1, Technical Description
Example:
Target frequency:
30 MHz
Tolerance:
8 ns
Software setting:
25 MHz (1 / (4 x (8 ns + 2 ns)) = 25 MHz)
The typical time delay value fort he cable is about 5 ns / m. Multiply this by to
because of the to and from signal propagation.
Example 1:
Hardware configuration: Scan Trainer II (GOEPEL) as UUT plus 50 cm flat cable to controller:
Cable delay + UUT delay = 2 x 2.5 ns + 10 ns = 15 ns
The UUT delay was theoretically calculated and proved by measuring: 10 ns.
Note: Measure the UUT delay:
- set the TCK frequency <= 1 MHz in SYSTEM CASCON
- scope channel 1 to TDO of the UUT
- scope channel 2 to TCK of the UUT
- trigger the scope with channel 1 (no matter which edge)
The t
delay
is the time between falling edege of the TCK and a change of TDO
t
delay
TCK
TDO
Figure 15: Measure the UUT TCK-TDO delay
Summary of Contents for SFX-TAP2/C
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