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Possible values:
•
0 - priority of the internal receiver (by default);
•
1 - priority of the external receiver;
•
2 - source selection based on HDOP level
.
To determine the type of source currently used (internal receiver or
external antenna), the GPS Power I/O-element is used (bit mask,
ID_Send 69). The bit width of this parameter is 1 byte.
The bit mask is calculated as follows: zero nibble - for the internal
receiver, the first nibble - for the external receiver. Byte order - from low
to high (little-endian, right to left):
•
Bit 0 - the receiver is configured;
•
Bit 1 - GPS signal present;
•
Bit 2 - signal source activity;
•
Bit 3 - the bit is not used;
For example:
The value of param69 = 115 is transmitted to the server. We
convert the number 155 from DEC to BIN and get the value 0111 0011.
For 0011 (zero nibble):
1 - the receiver is configured;
1 - there is a GPS signal;
0 - the source is not active;
0 - the bit is not used;
For 0111 (first nibble):
1 - the receiver is configured;
1 - there is a GPS signal;
1 - the source is active;
0 - the bit is not used;
Based on this data, it can be established that the external antenna
is currently used as a source for determining GPS data.
