ashtech ZY-12 Information Supplement page 54

Parameter
STHE The reference station health, set on the RTCM Options screen (base mode) or
received from the base station.
SYNC Indicates that the receiver is synchronous with a message. It has decoded a
message, captured its sequence number (SQNU), and found that its parity
was good.
The receiver displays a question mark (?) when a given message does not
carry the next sequential number expected by the receiver. The question mark
may be displayed for the first message since there is no previous message
with which to be in sequence.
SQNU The RTC, message sequence number, generated by the base or received by
the remote receiver.
ZCNT is the RTCM message Z-count.
FLEN Contains the RTCM message frame length.
PRN The satellite PRN number.
PRC The pseudo-range correction in meters. Negative numbers are shown in
inverse video.
RRC The range-rate correction in centimeters per second. Negative numbers are
shown in inverse video.
IODE The issue of the data.
S/UD The scale factor and user-differential range error.
AGE For remote mode, shows the age of received messages in seconds. In base
mode, gives the time elapsed in seconds since the beginning of the
transmission of a type 1 message until a new type 1 message is generated.
QA The communication-quality factor, defined as:
(number of good messages / total number of messages) x 100
OFFSET The number of bits from the beginning of the RTCM byte in case of bit
slippage.
48
Table 3.18. Message Parameters (continued)
Description
ZY-12 GPS Receiver