In PicBasic, the support for the LCD is built into the language, and I don't have access to it's source code.
The methods to read has two parameters, the first is the address to read from the LCD, usually $80 or $C0 for the first and second lines respectively. The second parameter is an array of characters, where the LCD characters were placed.
Examples for reading from the LCD:
LCDIN $80, [ InArray[20], InArray[21], InArray[22], InArray[23],_
InArray[24], InArray[25], InArray[26], InArray[27],_
InArray[28], InArray[29], InArray[30], InArray[31],_
InArray[32], InArray[33], InArray[34], InArray[35] ]
LCDIN $c0, [InArray[36], InArray[37], InArray[38], InArray[39],_
InArray[40], InArray[41], InArray[42], InArray[43],_
InArray[44], InArray[45], InArray[46], InArray[47],_
InArray[48], InArray[49], InArray[50], InArray[51] ]
I'll read the Fujitsu documentation and figure it out for the Arduino. Wish I had other source code to access as a guide. Maybe from the mfg. Thank you.