9-2 Communication method
[1]Data link (standard function)Each station sends data in its sending area cyclically and stores data received from other stations in its receiving area.
Station number 00(8) Station number 01(8) Station number 02(8) Station number 03(8)
: Sending area
: Receiving area
For the JW-20CM to execute automatically these sending and receiving procedures, a special program for communication is required. Data link have relay link and register link. They can use at the same time.
Function | | Contents |
| | |
Relay link | N: M communication | Total no. of link points : 2048 max. (256 bytes) |
| | |
Register link | N: M communication | Total no. of link bytes : 2048 max. |
| | |
(1)Relay link functionMainly used for sending and receiving ON/OFF information
[Example] In the case of sending 1-byte data from a master station and slave stations 01 and 02.
Master station (PC00)Slave station (PC01)Slave station (PC02)
コ0200 コ0201 コ0202
PC00 Program | PC01 Program | PC02 Program |
9 | 02000 | 02000 |
02000 | |
:Send
:Receive
02010 | 02010 |
| 02010 |
02020 | 02020 |
02020
•The link relay of the receiving station must be programmed as input signal by the PC program- ming. Also, it may be used as source (S) side of application instruction.
•The sending and receiving data correspond in bits of one point unit.
| 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 | | 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 |
コ0200 | | | | | | | | | コ0200 | | | | | | | | | |
| | | | | | | | | | Is the same value as コ0200 of the master station. |
| 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 | | 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 |
コ0201 | | | | | | | | | コ0201 | | | | | | | | | |
Is the same value as コ0201 of the slave station.