ashtech G12 - MSV: Minimum Satellites for Raw Measurement Output

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Commands
CT1: Combined Measurement/Position Data (Format 1)
$PASHS,RAW,CT1,[c1],s2,[f1]
This command enables or disables the combined measurement and position data
message format 1, where c1 is port A, B or C (optional port), s2 is ON or OFF, and
f1 is the optional numeric output interval setting supporting a range of 0.05 to 999
seconds, depending on the measurement update rate option installed.
$PASHQ,CT1,[c1]
This command allows you to query a combined raw data message in the CT1 data
structure, which contains elements derived from the MCA and PBN messages.
c1 is the optional port designator for the response. If a port is not specified, the
receiver sends the response to the current port.
$PASHR,CT1
This message is not output unless the receiver is tracking at least one satellite. The
CT1 message contains an adjusted receive time (the time at which the data was
received) with satellite PRN numbers and channel assignments in association with
smoothed pseudoranges. This message contains data for a maximum of six
satellites. If the receiver is tracking more than six satellites, two CT1 messages are
output. The message is output in the format:
$PASHR,CT1,<Format 1 Data String + Checksum>
Table 4.56 defines the data string format.
Table 4.56. $PASHR,CT1 Data String
Binary Type Bytes Content
Long [adj_rcvtime] 4 The time at which the data was received, based on the following formula
using the rcvtime and navt values from the PBN message: adj_rcvtime =
rcvtime - navt/speed of light
char [sv_no] 1 The number of satellites in the message (1...6).
char [remainder] 1 The number of satellites remaining for the current epoch; i.e., since the
CT1 message can contain data for a maximum of six satellites, if the
receiver is tracking eight satellites, two are remaining
char [chn1] 1 Channel (1...12)
char [prn1] 1 Satellite PRN number
double
[smooth_rng1]
8 Smoothed pseudorange measurement, derived from raw range data and
smoothing as defined in the MCA message
char [chn2] 1 Channel (1...12)
char [prn2] 1 Satellite PRN number
G12RevD.book Page 117 Tuesday, April 2, 2002 4:33 PM