URIBeacon2Service Needs initial AdvertisedTxPowerLevels

[schilit]

Hi @rgrover @roywant

The UriBeaconConfigService (or the main.c) requires a default array for Advertised Tx Power Levels. Indexing by the current mode results in the dBm value transmitted in the ADV packet.

Since the value used for nRF51822n::setTxPower may not be the same as the Advertised value we also recommend an array for this purpose.

nRF51822n::setTxPower takes values of -40, -20, -16, -12, -8, -4, 0, 4

Suggest

// Values included in ADV packets for
// TX_POWER_MODE_LOWEST through TX_POWER_MODE_HIGH
// TODO: adjust these values using measurements for the packaged device
uint8_t[4] advertisedTxPowerLevels = {-40, -20, -12, 4};

// Values for nRF51822n::setTxPower for
// TX_POWER_MODE_LOWEST through TX_POWER_MODE_HIGH
uint8_t[4] firmwareTxPowerLevels = {-40, -20, -12, 4};

[rgrover]

Not clear what's needed or appropriate here. Mbed would like to abstract the underlying controller. We shouldn't depend on or encode particularities.

[schilit]

If Mbed is trying to abstract out the particulars then perhaps it should offer the LOWEST, LOW, MEDIUM, HIGH abstraction.

The way it is now the caller of setTxPower needs to know the valid firmware values. The nRF51822::setPower only accepts certain values!

Another abstraction for Mbed might be a functions getFirstTxPowerValue() and getNextTxPowerValue() which is chip dependent.

[rgrover]

This has been resolved. Refer to https://github.com/ARMmbed/BLE_API/blob/master/ble/services/URIBeaconConfigService.h#L47. Please re-open if required.