Galil Motion Control CDS-3310, Руководство пользователя

Страница: 41 / 166

CDS-3310 Chapter 4 Communication
i
33
Notes Regarding Velocity and Torque Information
The velocity information that is returned in the data record is 64 times larger than the value returned
when using the command TV (Tell Velocity). See command reference for more information about
TV.
The Torque information is represented as a number in the range of +/-32767. Maximum negative
torque is -32767. Maximum positive torque is 32767. Zero torque is 0.
QZ Command
The QZ command can be very useful when using the QR command, since it provides information
about the controller and the data record. The QZ command returns the following 4 bytes of
information.
BYTE # INFORMATION
0 Number of axes present
1 number of bytes in general block of data record
2 number of bytes in coordinate plane block of data record
3 Number of Bytes in each axis block of data record
Controller Response to Commands
Most CDS-3310 instructions are represented by two characters followed by the appropriate parameters.
Each instruction must be terminated by a carriage return or semicolon.
Instructions are sent in ASCII, and the CDS-3310 decodes each ASCII character (one byte) one at a
time. It takes approximately 0.5 msec for the controller to decode each command. However, the PC
can send data to the controller at a much faster rate because of the FIFO buffer.
After the instruction is decoded, the CDS-3310 returns a response to the port from which the command
was generated. If the instruction was valid, the controller returns a colon (:) or a question mark (?) if
the instruction was not valid. For example, the controller will respond to commands which are sent via
the main RS-232 port back through the RS-232 port, and to commands which are sent via the Ethernet
port back through the Ethernet port.
For instructions that return data, such as Tell Position (TP), the CDS-3310 will return the data followed
by a carriage return, line feed and colon.
It is good practice to check for : after each command is sent to prevent errors. An echo function is
provided (serial only) to enable associating the CDS-3310 response with the data sent. The echo is
enabled by sending the command EO 1 to the controller.
Unsolicited Messages Generated by Controller
When the controller is executing a program, it may generate responses which will be sent via the main
RS-232 port or Ethernet ports. This response could be generated as a result of messages using the MG
or IN (serial only) command OR as a result of a command error. These responses are known as
unsolicited messages since they are not generated as the direct response to a command.
Messages can be directed to a specific port using the CF command or using the specific Port arguments
– see MG and IN commands described in the Command Reference. If the port is not explicitly given,
unsolicited messages will be sent to the default port.