add power testing notes for eink

src/gps/Air530GPS.cpp

@@ -75,13 +75,13 @@ void Air530GPS::sleep() {
 /// wake the GPS into normal operation mode
 void Air530GPS::wake()
 {
-#if 0
+#if 1
 #ifdef PIN_GPS_WAKE
     digitalWrite(PIN_GPS_WAKE, 1);
     pinMode(PIN_GPS_WAKE, OUTPUT);
 #endif
 #else
-    // For power testing
+    // For power testing - keep GPS sleeping forever
     sleep();
 #endif
 }

variants/eink/variant.h

@@ -53,7 +53,8 @@ feedback to give:
 
 * remove ipx connector for nfc, instead use two caps and loop traces on the back of the board as an antenna?
 
-* the i2c RTC seems to talk fine on the i2c bus.  However, I'm not sure of the utility of that part.  Instead I'd be in favor of the following:
+* the i2c RTC seems to talk fine on the i2c bus.  However, I'm not sure of the utility of that part.  Instead I'd be in favor of
+the following:
 
 * move BAT1 to power the GPS VBACKUP instead per page 6 of the Air530 datasheet.  And remove the i2c RTC entirely.
 
@@ -65,6 +66,20 @@ This would allow using 4 bit wide interface mode to the serial flash - doubling
 https://infocenter.nordicsemi.com/topic/ug_nrf52840_dk/UG/nrf52840_DK/hw_external_memory.html?cp=4_0_4_7_4
 Once again - I'm glad you added that external flash chip.
 
+* Power measurements
+When powered by 4V battery
+
+CPU on, lora radio RX mode, bluetooth enabled, GPS trying to lock.  total draw 43mA
+CPU on, lora radio RX mode, bluetooth enabled, GPS super low power sleep mode.  Total draw 20mA
+CPU on, lora radio TX mode, bluetooth enabled, GPS super low power sleep mode.  Total draw 132mA
+
+Note: power consumption while connected via BLE to a phone almost identical.
+
+Note: eink display for all tests was in sleep mode most of the time.  Current draw during the brief periods while the eink was being drawn was not
+measured (but it was low).
+
+Note: Turning off EINK PWR_ON produces no noticeable power savings over just putting the eink display into sleep mode.
+
 */
 
 /*----------------------------------------------------------------------------