Merge pull request #736 from ViezeVingertjes/t1000e-low-power

Introduce BLE low-power mode and enable DC/DC converter

Author: fdlamotte

src/helpers/nrf52/SerialBLEInterface.cpp

@@ -27,8 +27,8 @@ void SerialBLEInterface::begin(const char* device_name, uint32_t pin_code) {
 
   Bluefruit.configPrphBandwidth(BANDWIDTH_MAX);
   Bluefruit.configPrphConn(250, BLE_GAP_EVENT_LENGTH_MIN, 16, 16);  // increase MTU
+  Bluefruit.setTxPower(BLE_TX_POWER);
   Bluefruit.begin();
-  Bluefruit.setTxPower(4);    // Check bluefruit.h for supported values
   Bluefruit.setName(device_name);
 
   Bluefruit.Security.setMITM(true);
@@ -80,7 +80,7 @@ void SerialBLEInterface::startAdv() {
    * https://developer.apple.com/library/content/qa/qa1931/_index.html   
    */
   Bluefruit.Advertising.restartOnDisconnect(false); // don't restart automatically as we handle it in onDisconnect
-  Bluefruit.Advertising.setInterval(32, 244);    // in unit of 0.625 ms
+  Bluefruit.Advertising.setInterval(32, 1600);
   Bluefruit.Advertising.setFastTimeout(30);      // number of seconds in fast mode
   Bluefruit.Advertising.start(0);                // 0 = Don't stop advertising after n seconds
 

src/helpers/nrf52/SerialBLEInterface.h

@@ -3,6 +3,10 @@
 #include "../BaseSerialInterface.h"
 #include <bluefruit.h>
 
+#ifndef BLE_TX_POWER
+#define BLE_TX_POWER 4
+#endif
+
 class SerialBLEInterface : public BaseSerialInterface {
   BLEUart bleuart;
   bool _isEnabled;

variants/t1000-e/T1000eBoard.cpp

@@ -11,6 +11,9 @@ void T1000eBoard::begin() {
 
   sd_power_mode_set(NRF_POWER_MODE_LOWPWR);
 
+  // Enable DC/DC converter for improved power efficiency
+  NRF_POWER->DCDCEN = 1;
+
 #ifdef BUTTON_PIN
   pinMode(BATTERY_PIN, INPUT);
   pinMode(BUTTON_PIN, INPUT);

variants/t1000-e/platformio.ini

@@ -94,6 +94,7 @@ build_flags = ${t1000-e.build_flags}
   -D MAX_CONTACTS=350
   -D MAX_GROUP_CHANNELS=40
   -D BLE_PIN_CODE=123456
+  -D BLE_TX_POWER=0
 ;  -D BLE_DEBUG_LOGGING=1
 ;  -D MESH_PACKET_LOGGING=1
 ;  -D MESH_DEBUG=1