Hi amulya,
could you please share the part number of your 6,12 LCD module, coz so far I’ve seen only LCD module with specification 16,2 or 16,1 or 16,4 etc.
Anyway for your 6, 12 matrix, consider it as a linear array of 72 elements (6*12). Now you can start from 0th elemnt and store the 0th character coming in serially, increment the array elemnt to 1, store the 1th serial character….. do it till the 19th character is received.