600 REM CODE CONVERSION FUNCTIONS
605 :
610 :
615 :
650 REM FN PS(X):PETASCII->SCREEN POKES
655 REM FN SP(X):SCREEN POKES->PETASCII
660 REM FN CV(X):TRUE ASCII<->PETASCII
665 :
670 DEF FN P1(X)=X+128+128*(X>31)+64*(X>63)-32*(X>95)-96*(X>127)+128*(X>159)
675 DEF FN PS(X)=FN P1(X)+64*(X>191)+33*(X>254)
680 DEF FN SP(X)=X+64+64*(X>31)-128*(X>63)+64*(X>95)+192*(X>127)-64*(X>191)
685 DEF FN A1(X)=X+(X*(X>127))-126*(X>127)
690 DEF FN A2(X)=X-32*(X>64 AND X<91)+32*(X>96 AND X<123)+128*(X>192 AND X<219)
695 DEF FN CV(X)=FN A1(FN A2(X))