Save the file having wavelength in the first column and ∆ε values in second as a text (ASCII) file with the protein name “protein.txt”. Important : There should not be any other text or numbers except the data values and the file name should not be longer than 12 characters (including the file extension, .txt).
Copy this file (protein.txt) in the ‘CDPro' directory.
Open the directory, ‘CDPro'.
Double click the ‘CRDATA' application file; a window appears.
The window will have a set of questions/instructions; follow them as discussed in the subsequent steps.
Question/Instruction 1: Do you want to create a new INPUT file?
1. Type 0 for creating a new INPUT file and press ENTER.
Question/Instruction 2: Enter TITLE for your data –40 characters
1. Type the name of the protein you are studying (not more than 40 characters) and press ENTER.
Question/Instruction 3: The number of lines to be skipped in CD file

Enter the number of CD values per nm
1. Enter the correct number as suggested (this depends on the wavelength interval the data is recorded with) and press ENTER.
Question/Instruction 4: INPUT INITIAL wavelength
1. Enter the maximum wavelength the CD data is recorded at (do not type nm), and press ENTER.
Question/Instruction 5: INPUT INITIAL wavelength
1. Enter the minimum wavelength the CD data is recorded at (do not type nm), and press ENTER.
Question/Instruction 6: Is the data in Molar Ellipticity units?
1. Type the appropriate number and press ENTER (Note that the data we are using as input is in ∆ε form and therefore does not require any conversion for analysis by CDPro programs. Therefore, type 0 and press ENTER).
Question/Instruction 7: ASCII-file name (CD data)-MAX of 12 letters
1. Type the name of the file (with file extension) containing CD data (protein.txt in this case) and press ENTER (Note 1).