Update README.md

c-code/README.md

-## C library to create files in SNS-BIET2020 binary format
+# C library to create files in SNS-BIET2020 binary format
+
+There are two examples: **test_MPS** and **test_DBL**.
+
+1. #### MPS 
+   This example creates a file that contains faults belonging to a speicific trip.
+   It replicates structure from [SoftIOC > Errant > MPS > DTL_LLRF_HPM6_fault > 20200214_135209](https://ics-srv-web2.sns.ornl.gov/Diagnostics/index.php?dir=Instruments%2FSoftIOC%2FErrant%2FMPS%2FDTL_LLRF_HPM6_fault%2F20200214_135209%2F)
+
+1. #### DBL
+   This creates a ~10Mb file that stores waveforms.
+
+## Compilation 
+To compile **test_XXX** executable run following from **c-code** directory
+```bash
+gcc -o bin/XXX -I . test_XXX.c binary_storage.c
+```
+It will create executable **bin/XX**.
+You can run executable by
+```bash
+bin/XXX
+```
+Running an executable **XXX** will create a binary file named **test_XXX.bin**
+You can see contents of the binary files using python version of the library, *python3* is required
+```bash
+python3 ../py/test_read.py test_XXX.bin
+```