S7 Client

Name	S7 Client
Version	v1.0.1
DockerHub	weevenetwork/s7-client
Authors	Paul Gaiduk

Table of Contents

• S7 Client
  • Table of Contents
  • Description
  • Environment Variables
    • Module Specific
    • Set by the weeve Agent on the edge-node
  • Input
  • Output

Description

This module reads out the memory of a Siemens LOGO! controller at a specified interval and sends the read values labeled with the respective virtual memory addresses to the next module. The implementation is based on the python-snap7 library.

Environment Variables

Module Specific

The following module configurations can be provided in a data service designer section on weeve platform:

Environment Variables	type	Description
LOGO_IP	string	IP address at which the LOGO! controller can be reached
LOCAL_TSAP	string	Local TSAP identifier
REMOTE_TSAP	string	Remote TSAP identifier (of the LOGO! controller)
PORT	int	Port number to reach the LOGO! controller
VM_ADDR	string	Comma-separated list of VM addresses to read. The address identifier should start with "V" followed by a number, with an optional "W" (word) or "D" (double-word) between them. For example "VD3" will read the third double-word (4 bytes), "VW46" - the 46-th word (2 bytes) and "V10" the 10th byte.
POLL_INTERVAL	int	Poll interval in seconds

Set by the weeve Agent on the edge-node

Other features required for establishing the inter-container communication between modules in a data service are set by weeve agent.

Environment Variables	type	Description
MODULE_NAME	string	Name of the module
MODULE_TYPE	string	Type of the module (Input, Processing, Output)
EGRESS_URLS	string	HTTP ReST endpoint for the next module
LOG_LEVEL	string	Allowed log levels: DEBUG, INFO, WARNING, ERROR, CRITICAL. Refer to logging package documentation.

Input

Output

Output of this module is a JSON with virtual addresses as lables followed by the bytes read from the LOGO! controller represented as integer numbers. Example:

{
  "VD1": 71,
  "V6": 0
}