SiP-external MIPI RFFE device control configuration %XMIPIRFFECTRL

The proprietary %XMIPIRFFECTRL command is used to configure the System in Package (SiP)-external MIPI RF Front-End Control Interface (RFFE) device register accesses in different phases of modem operation. v2.2.x

The device must first be introduced using the %XMIPIRFFEDEV command.

MIPI RFFE devices contain an internal register map described in the datasheet of the device. To control the device, the registers in the device must be written with valid values. The %XMIPIRFFECTRL command allows configuring the nRF91x1 SiP to write the device's registers. The register addresses, the values, and timing (phase) can be configured as described below.

The external MIPI RFFE control in nRF91x1 supports configuring the RFFE device for four different phases of RF operation. The phases are initializing (INIT), start receiving or transmitting (ON), stop receiving or transmitting (OFF), and going to sleep (PWROFF).

The %XMIPIRFFECTRL command must be sent separately for each phase. It is not mandatory to configure all phases.

The %XMIPIRFFECTRL command must be sent before any modem activity occurs.

The %XMIPIRFFEDBG command can be used to debug MIPI RFFE configurations by reading or writing to device registers.

The phases are defined as follows:

INIT

Applied when RF is waking up. INIT is frequency-agnostic. Controls up to four MIPI RFFE device registers. The main purpose is to allow preparation or activation of the MIPI RFFE device if activation requires long settling.

ON

Applied when RF is starting for a specific frequency or when LTE-M frequency hopping is performed by the modem RF. Controls a maximum of two frequency-agnostic registers that can be used for device activation, for instance. This phase also controls a maximum of two registers whose value can be defined to depend on the RF frequency of the modem. The table for the frequency-dependent control can have a maximum of 64 frequencies.

OFF

Applied when RF is stopping. The configuration is frequency-agnostic. Controls up to four MIPI RFFE device registers.

PWROFF

Applied when RF is going to sleep. The configuration is frequency-agnostic. Controls up to four MIPI RFFE device registers. The main purpose is to deactivate the MIPI RFFE device.