Seneca S6001-RTU, User Manual

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USER MANUAL – Z-TWS4/Z-PASS2-S/S6001-RTU
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In the Device FW, a daemon is running which:

parses the CGI requests

reads/writes the requested variables from/to the shared-memory

gives back the values/results in the CGI responses
Two CGIs are defined, one to read and one to write variables, as described in the following.
Both CGIs shall be inserted into HTTP POST requests.
It is important to note that, as far as the variables properties are concerned, normally the application
sending the CGIs doesn’t need to know the offset, size and format of a variable, while it needs to know the
variables names and, possibly, the variables modes, to tell which variables can be read/written and which
can only be read.
21.3.1 CGI “readVariable”
To read one variable:
request:
goform/readVariable?nVars=1&var1=<var_name1>
response:
#<var_name1> <var_code1> <var_add_info1>
<var_value1>
Example:
request:
goform/readVariable?nVars=1&var1=M1_Output_1
response (successful case):
# M1_Output_1 0
1
response (failure case):
# M1_Output_1 5 Operation timeout
The CGI can be extended to read N variables (N>1), for example to read 2 variables:
goform/readVariable?nVars=2&var1=<var_name1>&var2=<var_name2>
The response contains N sections with the format described above.
21.3.2 CGI “writeVariable”
To write one variable:
request:
goform/writeVariable?nVars=1&var1=<var_name1>&value1=<var_value1>
response:
#<var_name1> <var_code1> <var_add_info1>
Example: