Update README.md

README.md

@@ -1,5 +1,5 @@
 # Binary Hexadecimal Conversion
-Convert hex to binary and binary to hex
+Convert hex to binary and binary to hex by slicing inputs & outputs into 4-bit nibbles
 
 ##Notes
 - Choose to which direction to convert
@@ -8,3 +8,12 @@ Convert hex to binary and binary to hex
 ##Limitations
 - 32-bit binary input  
 Not really an issue, since you can simply change `MAX_BITS_ALLOWED` to allow infinite sequences of 0's and 1's
+
+##Code Details
+- Uses 2 dictionaries of 4-bit nibbles to convert both ways
+- Robust error handling checks:
+  - Binay input is <= 32 bits
+  - Empty string input is correctly returns 0000 binary or 0 hex
+  - Hex is converted to uppercase to avoid duplicate dictionary keys for lowercase
+  - Binary input is validated to make sure it is only 0's and 1's
+  - Hex input catches KeyErrors if the input is not a value 0-9 or A-F

binary-hexadecimal-conversion.py

@@ -36,8 +36,11 @@
     'D':'1101', 
     'E':'1110', 
     'F':'1111' }
+
 MAX_BITS_ALLOWED = 32       #used to limit user input
 NIBBLE_SIZE = 4             #half a byte. (4 digits long of 1's and 0's)
+
+
 def showWelcomeScreen():
     userChoice=input('\n\tHex & Binary Converter \nEnter 1 to convert unsigned binary to hexadecimal \nEnter 2 to convert hexadecimal to unsigned binary \nQuit (any other character) \nYour choice: ')
     userChoice=userChoice.lstrip(' ')   #remove leading spaces