Analog Devices ADRV9001 User Manual page 114

Reference Manual
FREQUENCY HOPPING
At initialization, assign up to 6 DPGIO pins to provide 64 possible indices to the current hopping table. During operation, set the DGPIO pins
prior to the upcoming hop edge. At each hop edge, the ADRV9001 samples the DGPIO pins to understand the hopping table entry to use.
Figure 107 shows an example of table indexing using four DGPIO pins with the PLL Mux mode. At the hop edge, the ADRV9001 samples the
DPGIO pins and one PLL retunes to the new frequency starting from the same hop edge.
The following restrictions apply to this mode:
Each DGPIO pin represents a bit in the index, and the ADRV9001 samples each assigned pin to form a full index to the table.
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The ADRV9001 expects that the lower DPGIO number is the LSB of the index.
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Assign adjacent DGPIO pins (for example, cannot assign DGPIO-0 to Bit 0, and DPGIO-11 to Bit 1, and so on).
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The ADRV9001 samples the DGPIO pins at every hop edge. It uses any index if the sampled index is deemed valid (meaning, provide a
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valid index to the frequency hopping table). Therefore, ensure to load the correct table entries and assign the appropriate number of GPIO
pins to avoid having an index that is out of boundary.
Hopping Table Switching Method: Automatic Ping Pong vs. Manual Switch
As mentioned earlier, the ADRV9001 allows to define up to two hopping tables. In any FH mode, the ADRV9001 allows to switch between these
two hopping tables, if both are defined. Use the following rules to switch tables:
When a table is switched, the index to the new table is set to 0 by the ADRV9001.
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The new table is read at the next hop signal edge.
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Automatic Table Ping Pong Switch
The automatic ping pong mode works like the regular automatic increment mode. However, once the end of one table is reached, the
ADRV9001 automatically switches to the other table. In this way, continuously increment through, at most, 128 table entries/hop frequencies.
This mode does not require any external signal. The ADRV9001 automatically switches between the two tables.
Manual Switch with Automatic Increment
Switch between the two hopping tables at any time manually using an API or a DGPIO pin.
Configure the DGPIO pin to switch the hopping table at initialization. Besides using DGPIO, issue an API to switch between the two tables.
In the DGPIO mode, when the hopping table select pin is low, table A is set as the active table, and when the hopping table select pin is set
high, table B is set as the active table. The falling or rising edge of HOP Table Select signals the switch to the A or B table, respectively.
Figure 108 shows that the HOP Table Select pin is sampled at the hop edge. Set the HOP Table Select pin before the upcoming hop edge. The
ADRV9001 resets the hopping table index to zero upon switching. In other words, when switching between tables, the new table always starts
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Figure 107. DGPIO Table Indexing with PLL Mux Mode
ADRV9001
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