S113 vs S140 TX power

[A.P]

Hi!

We're running the NRF52840 chipset on a custom board. I've recently switched from running the S140 softdevice to running S113 softdevice on our peripherals in order to save space.

I'm now trying to set the peripherals' TX to the max possible, which for the nrf52840 should be 8dBm. Going over the S113 and S140 softdevice documentations, I see the sd_ble_gap_tx_power_set(...)  allowed TX power is -40dBm, -20dBm, -16dBm, -12dBm, -8dBm, -4dBm, 0dBm, +3dBm and +4dBm on S113, but -40dBm, -20dBm, -16dBm, -12dBm, -8dBm, -4dBm, 0dBm, +2dBm, +3dBm, +4dBm, +5dBm, +6dBm, +7dBm and +8dBm on the S140 softdevice.

Am I misunderstanding something? If not, is there a way to bypass this so that I can use the full chip capabilities?

Thanks!

[Jørgen Holmefjord]

Hi,

Unfortunately, +8 dBm is currently not supported in the s113 softdevice. We are aware of the issue and it may be fixed in a future release. Please contact your regional sales manager for details on roadmaps and future releases.

There is no way to access the RADIO peripheral directly to override this. Access to the RADIO peripheral is controlled by the softdevice, writing any registers will cause an assert.

Best regards,
Jørgen