Control Unit
Message to/from PLC | |
Description | This control unit receives messages sent by the CNC to the PLC and messages sent by the PLC to other users of the communication process provided by the CNC. The CNC can send a message to the PLC via the commands #MSG PLC ["…"] or #MSG SYN PLC [“...”] (see [PROG]). The information on which of the commands was used to send a message is also sent in the user data of this control unit. |
Data type | MC_CONTROL_MSG_UNIT, see description Control Unit with usage check |
ST path | gpCh[channel_idx]^.msg_mc_control |
Commanded, requested data | |
ST element | .command_w .request_r |
Data type | |
Access | PLC writes command_w and reads request_r |
Flow control of commanded value | |
ST element | .command_semaphor_rw |
Data type | BOOL |
Value range | [TRUE, FALSE] |
Special features | Consumption data item |
Access | PLC can write data for commanding if command_semaphor_rw has the value FALSE. When all command data is written, the PLC sets command_semaphor_rw to TRUE. CNC takes the commanded data if command_semaphor_rw is TRUE and then sets the flag to FALSE. |
Flow control of requested data | |
ST element | .request_semaphor_rw |
Data type | BOOL |
Value range | [TRUE, FALSE] |
Special features | Consumption data item |
Access | The data requested by the GUI can be written if request_semaphor_rw is FALSE. This element is then set to TRUE. PLC reads the data requested by GUI if request_semaphor_rw is TRUE. After the PLC fully accepts the data, the PLC sets this element to FALSE. |
Redirection | |
ST path | .enable_w |