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ashtech DG16
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198 DG14 and DG16 Board & Sensor Reference Manual
If the command is set without a period, the DG16 uses the period set by the
$PASHS,RCI command If the $PASHS,RCI command is issued after this message
period has been set, the period resets to the RCI setting.
$PASHR,MCA
This message is not output unless the receiver is tracking at least one satellite. The
MCA message contains some of the same measurement information as is
contained in the MBN message: doppler, raw pseudo-range, full carrier phase,
satellite PRN number, elevation, and azimuth. A separate MCA message is output
for each satellite being tracked. The structure of the message is in the format:
$PASHR,MCA,<Ashtech type 3 data string + checksum>
Table 7.8 outlines the data string format.
Table 7.8. $PASHR,MCA Data String
Field Bytes Content
unsigned short
[sequence tag]
2 Sequence ID number in units of 50 ms, modulo 30 minutes
unsigned char [left] 1 Number of remaining MCA messages to be sent for current epoch
unsigned char [svprn] 1 Satellite PRN number (1 to 32 for GPS and 33 to 64 for SBAS)
unsigned char [elev] 1 Satellite elevation angle in degrees
unsigned char [azim] 1 Satellite azimuth angle in increments of 2 degrees
unsigned char [chnind] 1 Channel (1 to 14) assigned to the satellite
unsigned char
[warning]
1 Warning flag:
Bit 1 set - See note below
Bit 2 set - See note below
Bit 3 set - Carrier phase questionable
Bit 4 set - Code phase questionable
Bit 5 set - Code phase integration questionable
Bit 6 set - Not used
Bit 7 set - Possible loss of lock
Bit 8 set - Loss of lock; counter reset
The interpretation of bits 1 and 2 is as follows:
[Bit 1, Bit 2]
[0, 0] Same as 22 in good/bad flag (see next field)
[1, 0] Same as 23 in good/bad flag
[0, 1] Same as 24 in good/bad flag
Note that more than one bit may be set at the same time, e.g., if bits
1, 3, and 6 are set at the same time, the warning flag is 37 (1 + 4 + 32)

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