3.5.4.3 Power Amplifier Registers

The following registers are used by the power amplifier.

The RF front-end registers from the following table and TX DSP registers from Figure 3-48 must not be changed by application software. The firmware controls these bits during the start-up and power-down phases of the transmit path.

Table 3-44. RF Front-End Registers Used by Firmware

Register

Function

FEEN2.PAEN

Power amplifier enable (bias only)

FECR.ANPS

ASK/DPSK switch (always set to ASK = 1)

Table 3-45. TX DSP Registers Used by Firmware

Register

Function

FSCR.SFM

Select FSK modulation

FSCR.TXMOD

Transmit modulation

FSCR.TXMS[1:0]

Transmit modulation source

The RF front-end values, summarized in the following table, are transferred from the factory-locked EEPROM to the RF front end by firmware before activating the power amplifier.

Table 3-46. RF Front-End Registers for Factory-Locked Calibration

Register

Function

FETN4.RTN4[3:0]

Resistor tuning value 4-bit

The RF front-end registers from the following table are changed by application-specific settings. The EEPROM content determines these register settings for each application. The configuration tool must be used to calculate these EEPROM settings.

Table 3-47. RF Front-End Registers Used for Application Settings

Register

Function

FEPAC.PACR[7:0]

Power amplifier control register, only PACR[5:0] used, PACR[7:6] must be ‘0’