Ntpollnetwork polling rate, Ntpoll network, Polling rate – Parker Hannifin GEM6K User Manual
Page 30: Ntpoll
3. Map a range of integer elements in the AB PLC to a range of integer (
VARI
) variables in the 6K (
NTMPWI
command).
4. Start polling the AB device at a specific polling interval (
NTPOLL
command). This updates integer data elements
in the AB PLC with the data from the mapped
VARI
variables in the 6K.
NOTE: The
VARI
variables in the 6K are 32 bit values, but the integers in the AB PLC are 16 bit values.
Therefore, the range for the
VARI
variables must be kept in the range –32767 to +32767.
Saved in Non-Volatile Memory
This command is saved in the controller’s non-volatile memory, and is remembered on power-up
and RESET.
Potential Error Conditions:
• You are not allowed to map the same 6K
VARI
variables for read and write functions. Nor are you allowed to map
the same 6K
VARI
variables to another PLC. If you attempt either of these conditions, the 6K will not accept the
NTMPWI
command and will transmit the error message “
VARIABLE MAPPING CONFLICT…
”.
• If you attempt to write to an AB data file of the wrong type, or to a non-existent data element, the 6K will not
accept the
NTMPWI
command, it will transmit the error message “
ERROR, INVALID FILE TYPE, NUMBER OR
SIZE…
” and it will automatically stop polling all mapped binary and integer variables (equivalent to executing the
NTMPRBi,i,0,i
,
NTMPWBi,i,0,i
,
NTMPRIi,i,0,i
, and
NTMPWIi,i,0,i
, commands).
Control over Polling: If you want to stop the 6K from writing integer data to the PLC, but continue to exchange
NTMPRI
,
NTMPRB
and
NTMPWB
data, use the
NTMPWIi,i,0,i
command. If you need to stop polling all mapped variables, use the
nNTPOLL0
command.
Example:
2NTIP1,172,54,125,34
; Identify network server #2 as an Allen-Bradley PLC at
; IP address 172.54.125.34
2NTCONN1
; Attempt connection to network server #2
2NTMPWI9,0,15,20
; File 9, elements 0-14, in the AB PLC are mapped to
; the 6K's integer variables VARI20-VARI34
2NTPOLL50
; Start polling network server #2, set interval to 50 ms
VARI = 42
; The value of AB file 9, element 5, will be set to 42,
; because it is mapped to VARI25
NTPOLL
Network Polling Rate
Type:
Network
Product Rev
Syntax:
Units:
n = network server #
i = polling rate (milliseconds)
Range:
n = 1-6
i = 0 (disable polling) or 1-9999 (50 is recommended)
Default:
0 (disabled)
Response:
1NTPOLL: *1NTPOLL50
See Also:
NTIP, NTCONN, NTMPRB, NTMPRI, NTMPWB, NTMPWI
6K 5.3
The
NTPOLL
command establishes the rate at which the 6K polls the Ethernet server devices for information:
• Allen-Bradley
PLC
Devices:
NTPOLL
sets the rate at which the 6K reads and writes the
VARI
and
VARB
variables
that are mapped to the Allen-Bradley PLC. Variables are mapped with the
NTMPRB
,
NTMPRI
,
NTMPWB
and
NTMPWI
commands.
• OPTO22:
NTPOLL
sets the rate for polling or changing the states of the input and output modules on the OPTO22.
OPTO22 outputs are controlled with the
\OUT
and
\ANO
commands, and the inputs are monitored with the
\IN
,
\ANI
,
\TANI
,
\TANO
,
\TIN
,
\TIO
,
\TOUT
commands.
The polling rate affects the 6K overall command execution speed (slowing the polling rate will speed up the 6K’s
command processing).
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