2 Functions of Devices in DVP-PLC e) Set up the start communication address of the Slave to be read/written. (See the explanations above on special D). The default start communication address of Slave to be read: H1064 = D100. The default start communication address of Slave to be written: H10C8 = D200. f) Operation procedure: i) Enable the function of more than 32 stations connected to PLC LINK and reading/writing of 16 data (Max. 100 data) (M1353). ii) Enable reading/writing of PLC LINK in the same polling (M1354). iii) Set up PLC LINK as auto mode (M1351), or manual mode (M1352) and the times of polling (D1431).
iv) When M1355 = On, M1360 ~ M1375 (M1440 ~ M1455) will be the flags for the PLC designated to be connected to. When M1355 = Off, there will be detection on the slaves connected, and M1360 ~ M1375 (M1440 ~ M1455) will become the flags for the existence of connected PLC. v) Enable PLC LINK (M1350). 9. How does Master PLC work: a) To detect station No. of Slave: Set up the LINK to be automatic mode (M1351 = On) or manual mode (M1352 = On) (Note: M1351 and M1352 cannot be “On” at the same time) When M1350 = On, Master PLC starts to detect the total number of Slave stations connected to the LINK and records the number in D1433.
The detection time may differ upon the number of Slave stations and the setting of communication timeout in D1129. b) When M1360 ~ M1375, M1440 ~ M1455 = On, Slave ID1 ~ ID32 exist. c) If the detected number Slave stations is 0, M1350 will be “Off” and the LINK will be stopped. d) M1353 and M1354 should be set before PLC LINK is enabled. When PLC LINK is executed, the two special M will not afftec the action of PLC LINK. e) When M1355 = On, M1360 ~ M1375 (M1440 ~ M1455) will be the flags for the PLC designated to be connected to.
Therefore, no matter how many PLCs are actually connected, the PLC LINK function will continue to send read/write instruction in cycle according to the designated flags. f) When 1353 = On, D1480 ~ D1607 (read/write buffer of SLAVE ID1 ~ 4) will be used for storing the No. of registers D for Slave ID1 ~ ID32, The No. of register D shall not be “> 9,900” or “ auto-set it as 9,900. The data length shall not be “ > 100” or “ g) When M1354 = On, set up Modbus Function H17 (synchronous read/write) for PLC LINK communication. If the number of written data is set to be “0”, the communication of PLC LINK will be automatically converted into Modbus Function H03 (read multiple words).
Similarly, if the number of read data is set to be “0”, the communication of PLC LINK will be converted into Modbus Function H06 (write 1 word) or Modbus Function H10 (write multiple words). h) If the number of read/written data > 16, the time for timeout (D1129) shall be > 500ms in case communication timeout may occur. i) After M1350 = On, Master PLC detects the ID of Slave E PLC only right after the LINK is enabled and will not detect the ID again afterward. j) After the detection on Slave PLCs is completed, Master PLC starts to read and write data from/into every Slave PLC. Please be noted that, Master PLC only reads/writes data from/into the detected Slave PLC.
DVP-PLC Application Manual 2-132