ADRV9009 and HMC624

Moved thread to TES GUI and Software Support for ADRV9009 forum

Yes, You can use these GPIO's for controlling external attenuator.

From UG:

3.3 V GPIO, Gain Table External Element Control
The gain table, as discussed in the Receiver Gain Control section, includes a 4-bit, external element control column. This control column can be used to control an external, digitally stepped attenuator (DSA), or the column can be used for low noise amplifier (LNA) bypass control. This feature is convenient for users that require external elements to the transceiver to change gain based on the gain table setting within the transceiver, particularly in AGC scenarios.
To enable the gain table external element control, take the following steps after device initialization:
1. Load a gain table with non-zero values in the external element control column.
2. Set the 3.3 V GPIOs to output mode with the TALISE_setGpio3v3Oe() function.
3. Set the 3.3 V GPIO source control to TAL_GPIO3V3_EXTATTEN_LUT_MODE with the TALISE_setGpio3v3SourceCtrl() function.
After these steps are performed, the following 3.3V GPIO pins express the value of the external element control column for a specific receiver: Receiver 1 uses GPIO_3P3_3 to GPIO_3P3_0, and Receiver 2 uses GPIO_3P3_7 to GPIO_3P3_4.
The external element control values expressed on these pins depends on the gain index setting and the gain table.