SAP function module an value parameters with variable

[geogou1973]

Hello, I try to upload a function module from SAP

I have the following script. 

When i put in the "value":"$bpcsvar"  parameter the file manually a have the data.

when i put the variable $bpcsvar i have no data.

The variable i have in the script is the following

let bpcsvar='FILE.txt';

[Z_TOTALS_BPCS_FILE_LT_TOTALS]:
LOAD *;
SQL {
"function":"Z_TOTALS_BPCS_FILE",
"output":"LT_TOTALS",
"parameters":
[
{ "direction":"out", "name":"LT_TOTALS", "optional":false },
{ "direction":"in", "length":70, "name":"LV_FILENAME", "optional":false, "type":"CHAR", "value":"$bpcsvar" }
]
};

//*****

Have anyone some idea how can i put the value of the variable in the value parameter in order to have the data ?

Thank you in advance.

[geogou1973 · Accepted solution]

I found the solution. I have to put  "value":"$(bpcsvar)"