Mode 5: With FIFO Empty, Shift-Out is Held HIGH
in Anticipation of Data
Sequence of Operation
1. FIFO is initially empty; Shift-Out goes HIGH.
2. Shift-In pulse loads data into the FIFO and IR falls. HF
rises propagation delay tX1 after the falling edge of SI.
3. OR rises a fall-through time of tFTO after the falling
edge of Shift-In, indicating that new data is ready to be
output.
4. Data arrives at output one propagation delay, tOD5,
after the falling edge of Shift-In.
5. OR goes LOW pulse width tOP after rising and HF
goes LOW pulse width tX3 after rising, indicating that
the FIFO is empty once more.
6. Shift-Out goes LOW, necessary to complete the Shift-
Out process.
Note: FULL is LOW; MRis HIGH; OE is LOW; tDOF = tFTO − tOD5. Data output transition—valid data arrives at output stage tDOF after OR is HIGH.
FIGURE 5. Modes of Operation Mode 5
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