Update Console/Receiver/Spectrum Instrumentation m4i.4451/readme.md

Console/Receiver/Spectrum Instrumentation m4i.4451/readme.md

@@ -29,7 +29,20 @@ void m4iset_(int16 *pvData, int32 *lMemsize, int32 *posttr)
     }
 ```
 
-The other two scripts **rec_m4i_fifo_tdfilter.f** and **rec_m4i_tdfilter_rms.f** implement the c routine. They need to be compiled with a Fortran complier. The first line in these files can be taken as an example i.e. copy and paste it into the OS terminal using the working folder. 
+The other two scripts **rec_m4i_fifo_tdfilter.f** and **rec_m4i_tdfilter_rms.f** implement the c routine. They need to be compiled with a Fortran complier. The first line in these files can be taken as an example i.e. copy and paste it into the OS terminal using the working folder. For example: 
+
+```console
+gfortran -O2 rec_m4i_fifo_tdfilter.f m4iset_extrig_rms.c -mcmodel=medium /usr/lib64/libspcm_linux.so -o rec_m4i_tdfltr
+```
+In order to use them you need to provide the receiver frequency range and desired output folder as follows:
+```console
+rec_m4i_tdfltr 297000000 297000000
+``` 
+The receiver has 10 seconds timeout, which can be adjusted by adjusting the integer in spcm driver function:
+```c
+spcm_dwSetParam_i32 (hDrv, SPC_TIMEOUT, 10000);
+```
+If receiver does not detect the trigger, it automatically starts recording 
 
 ## References