Added NOTACKNOWLEDGED

Author: PaulZC

examples/Example20_SendCustomCommand/Example20_SendCustomCommand.ino

@@ -2,7 +2,7 @@
  sendCustomCommand
  By: Paul Clark (PaulZC)
  Date: April 18th, 2020
- 
+
  License: MIT. See license file for more information but you can
  basically do whatever you want with this code.
 
@@ -61,7 +61,7 @@ void setup()
 
  // Let's configure the module's dynamic platform model as if we were using setDynamicModel
  // Possible values are:
- // 0 (PORTABLE), 2 (STATIONARY), 3 (PEDESTRIAN), 4 (AUTOMOTIVE), 5 (SEA), 
+ // 0 (PORTABLE), 2 (STATIONARY), 3 (PEDESTRIAN), 4 (AUTOMOTIVE), 5 (SEA),
  // 6 (AIRBORNE1g), 7 (AIRBORNE2g), 8 (AIRBORNE4g), 9 (WRIST), 10 (BIKE)
 
  // Let's create our custom packet
@@ -85,6 +85,7 @@ void setup()
  // SFE_UBLOX_STATUS_DATA_RECEIVED if the data we requested was read / polled successfully
  // SFE_UBLOX_STATUS_DATA_SENT if the data we sent was writted successfully (ACK'd)
  // Other values indicate errors. Please see the sfe_ublox_status_e enum for further details.
+ // If you see a failure you can of course simply try sending the same command again.
 
  // Referring to the u-blox M8 Receiver Description and Protocol Specification we see that
  // the dynamic model is configured using the UBX-CFG-NAV5 message. So let's load our
@@ -101,9 +102,18 @@ void setup()
  // Now let's read the current navigation model settings. The results will be loaded into customCfg.
  if (myGPS.sendCustomCommand(&customCfg, maxWait) != SFE_UBLOX_STATUS_DATA_RECEIVED) // We are expecting data and an ACK
  {
- Serial.println(F("sendCustomCommand (poll) failed! Freezing."));
- while (1)
- ; 
+ Serial.println(F("sendCustomCommand (poll) failed! Trying again..."));
+ // We need to reset the packet before we try again as the values could have changed
+ customCfg.cls = UBX_CLASS_CFG;
+ customCfg.id = UBX_CFG_NAV5;
+ customCfg.len = 0;
+ customCfg.startingSpot = 0;
+ if (myGPS.sendCustomCommand(&customCfg, maxWait) != SFE_UBLOX_STATUS_DATA_RECEIVED) // We are expecting data and an ACK
+ {
+ Serial.println(F("sendCustomCommand (poll) failed again! Freezing."));
+ while (1)
+ ;
+ }
  }
 
  // Referring to the message definition for UBX-CFG-NAV5 we see that we need to change
@@ -133,7 +143,7 @@ void setup()
  {
  Serial.println(F("sendCustomCommand (set) failed! Freezing."));
  while (1)
- ; 
+ ;
  }
  else
  {