Blocks IPWatchdog
Back to Libraries
The pulse on EXEC triggers the IPWDG block. In the beginning ICMP/ARP request is send to the IP address. At the same time BUSY output changing the status of the log. 0 to 1, TMO_S running and block is waiting for response.
1. If a response is received during TMO_S, TMO_S is reseted. BUSY is set to log. 0, VALID is set to 1 (operation successful, output set) and Q is set to log. 1 (IP is available).
2. If the IP response is not received, BUSY remains in the log. 1 until TMO_S expires. After TMO_S expires BUSY goes to log.0, VALID goes to log.1 (operation successful, output set). Q remains in log. 0 (IP is not available).
Note:
EXEC should be set to a value greater than TMO_S to avoid unnecessary restart when the block cycle is not completed and waits for TMO_S.
IPWDG_ARP
Returns ARP ping status of given ip address
Asynchronous interface | ||||
in | IP_ADDR | string | ip address | |
in | TMO_S | int | timeout in seconds | |
out | Q | bool | status |
IPWDG_ICMP
Returns ICMP ping status of given ip address
Asynchronous interface | ||||
in | IP_ADDR | string | ip address | |
in | TMO_S | int | timeout in seconds | |
out | Q | bool | status |