Ethernet/IP PLC controller gateway

Contents

Ethernet/IP PLC controller gateway
- Setup
- EAPI methods
  - action
  - kill
  - terminate
  - var.get
  - var.set

Allows to communicate with Ethernet/IP-powered PLCs and other equipment.

Setup

Use the template EVA_DIR/share/svc-tpl/svc-tpl-controller-enip.yml:

# EthernetIP PLC controller gateway service
command: svc/eva-controller-enip
bus:
  path: var/bus.ipc
config:
  plc: 
    # only ab_eip is supported
    protocol: ab_eip
    host: 192.168.1.100
    port: 44818
    # PLC path
    path: "1,0"
    # PLC type, valid values are: LGX, MLGX, PLC, MLGX800
    cpu: LGX
  # panic on critical errors in X seconds after happened (0 - panic immediately)
  panic_in: null
  # default retry attempts for all operations (0 - no retries, give up if the
  # first attempt fails)
  retries: 2
  # an optional delay betwen writing tags and verifying written value
  #verify_delay: 0.1
  # event queue size, pull events ARE DROPPED on overflow. consider ALWAYS
  # having queue size > max possible tags pulled
  queue_size: 32768
  # ttl cache for pull events (sec, skip non-modified)
  pull_cache_sec: 3600
  # PLC pull interval, in seconds
  pull_interval: 1
  # pull blocks and parse maps
  #
  # the configuration is very similar (but extended) to the widely-used
  # https://github.com/alttch/pulr tool
  #pull:
    #- tag: test_array.test_float_array
      # An optional size/count args for PLC tag read commands, required for
      # arrays
      #size: 4
      #count: 10
      #map:
        #- offset: 0
          #oid: sensor:tests/test0
          # allowed types: real (REAL), real32, real64 (LREAL), uint8 (BOOL,
          # USINT), int8, sint8 (SINT), byte, uint16 (UINT), word, uint32
          # (UDINT), dword, sint16 (INT), int16, sint32 (DINT), int32, sint64
          # (LINT), int64, uint64 (ULINT), qword
          #type: real
        #  Offsets ARE NOT array indexes, but absolute offsets in block
        #  can be written as N+N+N
        #- offset: 0+4
          #oid: sensor:tests/test1
          #type: real
          #value_delta: 0.5 # report event only if the new value difference is >=
          #transform:
            #- func: multiply # multiply the value by N
              #params: [ 1000 ]
            #- func: divide # divide the value by N
              #params: [ 1000 ]
            #- func: round # round the value to N digits after comma
              #params: [ 2 ]
            #- func: calc_speed # use the value as calc-speed gauge (with N seconds delta)
              #params: [ 1 ]
            #- func: invert # invert the value between 0/1
            # #params: []
    # pull bits
    #- tag: test_array.test_bool_array
      #map:
        #- offset: 0/0
          #oid: sensor:tests/flag0
        #- offset: 0/1
          #oid: unit:tests/u1
  # action queue size, per item, actions on overflow are not dropped but wait
  # their attempt to enter the queue. The core marks an action as failed if it
  # does not enter the queue for <action timeout> seconds
  action_queue_size: 32
  # verify written data for actions
  actions_verify: true
  # OID map for actions
  #action_map:
    #unit:tests/u1:
      #tag: test_array.test_float_array[0]
      #type: real
timeout:
  # startup timeout should be slightly langer than default to allow the
  # controller prepare connection pool
  startup: 10
user: nobody
react_to_fail: true

Create the service using eva-shell:

eva svc create eva.controller.enip1 /opt/eva4/share/svc-tpl/svc-tpl-controller-enip.yml

or using the bus CLI client:

cd /opt/eva4
cat DEPLOY.yml | ./bin/yml2mp | \
    ./sbin/bus ./var/bus.ipc rpc call eva.core svc.deploy -

(see eva.core::svc.deploy for more info)

EAPI methods

See EAPI commons for the common information about the bus, types, errors and RPC calls.

action

Description	Executes a mapped unit action
Parameters	See Unit actions
Returns	See Unit actions

kill

Description	Attempts to terinate/cancel all actions for a unit
Parameters	See Unit actions
Returns	See Unit actions

terminate

Description	Attempts to terminate/cancel a unit action
Parameters	See Unit actions
Returns	See Unit actions

var.get

Description	Get En/IP tag from PLC
Parameters	required
Returns	Tag value, single or list

Parameters
Name	Type	Description	Required
i	String	PLC tag	yes
type	String	Data type (e.g. DINT)	yes
size	u32	Type size helper	no
count	u32	Count of data blocks (e.g. for arrays)	no
bit	u32	Get an individual bit	no
timeout	f64	Max operation timeout	no
retries	u8	Retry attempts	no

var.set

Description	Set En/IP tag on PLC
Parameters	required
Returns	nothing

Parameters
Name	Type	Description	Required
i	String	PLC tag	yes
value	Any	value to set	yes
type	String	Data type (e.g. DINT)	yes
bit	u32	Set an individual bit	no
verify	bool	Read the tag back and verify its value	no
timeout	f64	Max operation timeout	no
retries	u8	Retry attempts	no