Enable 3x DL NR-CA (FDD+FDD+FDD) on X65 modems with MPSS.DE.1.0 baseband firmware or newer:

This guide assumes you are already familiar with QPST and how to gain access to the diag port on your device. See this guide for enabling diag on various commercial UEs: Link

For an explanation on how hardware and software combinations are defined in Qualcomm firmware, see here.

Confirmed working with the following devices:

• Xiaomi 12S Ultra (2203121C, CN variant)
• Samsung Galaxy S22 Ultra (SM-S908U, SM-S908U1, US)

Devices with 3x DL NR-CA (FDD+FDD+FDD) enabled out of the box by the OEM:

• Xiaomi 12S Ultra (2203121C, CN variant)

_Note: 3x DL NR-CA (FDD+FDD+FDD) is only available in NR-SA

How to enable 3x DL NR-CA (FDD+FDD+FDD) in NR-SA

Step 1: Launch EFS explorer

Launch QPST with your device in diag mode. Then, open the EFS explorer.

Step 2: Upload the NV item files for 3x DL NR-CA (FDD+FDD+FDD)

Navigate to /nv/item_files/modem/nr5g/RRC/

Right click and “Copy item file from PC”, do not drag or drop.

List of NV item files:

cap_control_nrca_f_plus_f_band_combos set to 0x0101, defines a boolean where the first hex byte enables 2xDLCA and the second 3xDLCA

For dual SIM devices, also copy over the files suffixed by _Subscription01

Download from here