Code: (Select All)
_CONTROLCHR OFF
test$ = "abc"
a$ = B256to128$(test$)
b$ = B128to256$(a$)
PRINT test$, a$, b$
PRINT LEN(test$), LEN(a$), LEN(b$)
SLEEP
FOR i = 0 TO 255
t$ = CHR$(i)
PRINT i, t$,
a$ = B256to128(t$)
PRINT a$,
b$ = B128to256(a$)
PRINT b$
IF t$ <> b$ THEN
PRINT "DON'T MATCH!!"
END
END IF
NEXT
PRINT
PRINT "All characters match before and after encoding and decoding."
FUNCTION B256to128$ (text$)
FOR i = 1 TO LEN(text$)
a = ASC(text$, i) ' get the ASCII value of our character
b$ = RIGHT$("00000000" + _BIN$(a), 8) ' convert it to binary
temp$ = temp$ + b$ ' add the binary to a single long string
NEXT
padding$ = STRING$(7 - LEN(temp$) MOD 7, "0")
temp$ = temp$ + padding$ ' add necessay padding to make it suitable for base-128 encoding
FOR i = 1 TO LEN(temp$) STEP 7
c$ = MID$(temp$, i, 7) ' get 7 characters from our 8 byte represention
c = VAL("&B" + c$) ' that's the character value of our base 128-character
temp1$ = temp1$ + CHR$(c + 65) ' add that to our new string
NEXT
B256to128$ = temp1$
END FUNCTION
FUNCTION B128to256$ (text$)
FOR i = 1 TO LEN(text$)
a = ASC(text$, i) - 65
b$ = RIGHT$("0000000" + _BIN$(a), 7)
temp$ = temp$ + b$
NEXT
temp$ = LEFT$(temp$, 8 * INT(LEN(temp$) / 8)) 'remove padding
FOR i = 1 TO LEN(temp$) STEP 8
b$ = "&B" + MID$(temp$, i, 8)
temp1$ = temp1$ + CHR$(VAL(b$))
NEXT
B128to256$ = temp1$
END FUNCTION