Analog Devices ADRV9005 Reference Manual page 225

Reference Manual
POWER SAVING AND MONITOR MODE
enables all the buffer data to be retrieved by the user, so no information is lost. To use this mode, it is required to use a higher clock rate as
described in the Receive CSSI with Two, Four, and Eight Times Data Clock Rates
IQ data is constantly read out onto the SSI bus with no idle time until the buffer is emptied.
As described in the Signal FIFO
Note: this mode is currently only available in DMR profile and is limited to a 4x sample rate buffer read.
Enable External PLL
If using an external PLL, this needs to be enabled when the monitor mode enters the 'detecting' state. The ADRV9001 uses its
function to send a wakeup command to an external PLL. To use this function, set the SPI Main trigger source to 'Monitor' and upload the
required SPI data needed to enable the external PLL. Whenever the monitor mode enters the 'detecting' state, the SPI data will be transmitted
by the SPI main.
This feature allows further control of external components in monitor mode without the use of the BBIC. The BBIC is not needed in this process
so can stay in power saving mode.
An example of how to use this feature is given in the
Note: this feature is currently not enabled.
Reference Timer
In normal operation, the BBIC might uses a reference timer to synchronize timing between the base station and the mobile radio. When
the BBIC goes into sleep mode, this reference timer could be lost. The
mode operation and allow the BBIC to retrieve the reference timer when it wakes up. Before the monitor mode starts, the BBIC programs the
ADRV9002 to mimic the reference timer. The reference timer then stays active during the full monitor mode cycle. On wake of the BBIC, the
reference timer can be retrieved to synchronize its timing again.
There are two ways to set and retrieve the reference timer:
SPI mode: the reference timer value is written to the ADRV9001 via an API. Note that API writes are non-deterministic which may introduce
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inconsistency.
Pin mode: the reference timer is pulsed on a DGPIO which is read by the ADRV9001 to generate the reference timer internally. To retrieve
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the reference timer, the ADRV9001 pulses the timer onto a DGPIO for the BBIC to read.
Note: this feature is currently not available.
Monitor Mode with Frequency Hopping
Monitor mode can operate with frequency hopping. The difference between fixed frequency and frequency hopping in this mode is the
requirement to retune to different frequencies during the monitor mode operation. Frequency hopping can operate as normal in either PLL Mux
mode or PLL Retune mode. Monitor mode can continue to cycle between DETECTING and SLEEP states. When a valid signal is detected, the
wake-up procedure is started.
Since the ARM processor is needed to operate frequency hopping, the hop signals must align with the detecting cycle of monitor mode.
Alternatively, use power down modes 1 to 4 to keep ARM alive for the full monitoring cycle.
As the HOP signal needs to be externally generated by the BBIC, the BBIC will need to wake at least partially to send this signal and any other
necessary procedures to operate frequency hopping.
analog.com
section, the buffer depth is 2048.
Monitor Mode in TES GUI
section. When performing the fast buffer read operation, the
section.
ADRV9002 provides the ability to save this timer during the monitor
ADRV9001
SPI Main
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