ashtech DG14, Справочное руководство

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Basic Operation 31
Basic Operation
of commands you need to send to the DG16 to acquire the output you require for
you application.
Messages created by the user, using the UDM Utility, will respond with the ACK/
NAK message.
See Appendix A,
UDM Utility for more information on user-defined messaging.
The DG16 receiver has two primary RS-232 serial ports and one optional serial
port (available as a firmware option [R]) that support two-way, full-duplex
communication. The default protocol for transmitting or receiving data is 9600
baud, eight data bits, no parity, and one stop bit (8N1). The baud rate of the DG16
ports is adjustable using the
$PASHS,SPD speed set command; the data bit, stop
bit and parity protocol is always 8N1.
The optional third serial port can communicate at speeds up to 19,200 baud and
can be used as at TTL levels (standard) or RS-232 levels (load option).
All serial ports can be configured as TTL as an option instead of RS-232.
On initial power-up, or after issuing the $PASHS,INI (receiver initialization)
command or the $PASHS,RST (restore defaults) command, the default data rate
is 9600 baud for both standardized DG16 serial ports. Both are capable to
115,200 baud for data transfer.
The baud rates must be the same between the DG16 serial port and the serial
port on the device with which it is interfaced.
To maintain communication with the DG16 while changing the baud rate, issue the
$PASHS,SPD (set port speed) to change the baud rate of the DG16 port, then
change the baud rate of the command device to match the new baud rate setting
on the DG16 port.
DEFAULT SETTINGS
The default parameters for the DG16 serial Ports A and B:
•Baud Rate— 9600
•Data Bits— 8
•Stop Bits— 1
•Parity— None