The attached simple application controls the I/O scanning of an M580 PLC by manipulating the control bits.
There are four Modbus/TCP devices being scanned. They are scanned one at a time, each for 10 seconds. Basically a 10 second timer will be enabled while the control bit is set to 0. When the timer reached 10 seconds the control bit is set to 1 (turning off the scanner) the timer is reset and the next timer is enabled and the next control bit is set to 0 turning on scanning to the next device. When the fourth scan is finished the first one is enabled and so on.
There are four Modbus/TCP devices being scanned. They are scanned one at a time, each for 10 seconds. Basically a 10 second timer will be enabled while the control bit is set to 0. When the timer reached 10 seconds the control bit is set to 1 (turning off the scanner) the timer is reset and the next timer is enabled and the next control bit is set to 0 turning on scanning to the next device. When the fourth scan is finished the first one is enabled and so on.
Publié pour: Schneider Electric Belgium
