HP48SX 10 Print

GS (Randomly generate \ or /)
<< RAND -> x
  <<
    IF 'x>= .5'
    THEN 92 CHR
    ELSE 47 CHR
    END
  >>
>>

FLS (R: display row, L: line buffer, S: slash string)
<< -> R L S
  <<
      WHILE L SIZE 22 <
        REPEAT L S + 'L' STO
        GS 'S' STO
        L R DISP
      END
      L R STORL
  >>
>>

STORL (Stores contents of line buffer in associated global)
<<
  -> L R
  <<
    CASE
      R 1 SAME THEN L 'R1' STO END
      R 2 SAME THEN L 'R2' STO END
      R 3 SAME THEN L 'R3' STO END
      R 4 SAME THEN L 'R4' STO END
      R 5 SAME THEN L 'R5' STO END
      R 6 SAME THEN L 'R6' STO END
      R 7 SAME THEN L 'R7' STO END
    END
  >>
>>

SCROLL (shift everything up one line)
<<
  R2 'R1' STO R1 1 DISP
  R3 'R2' STO R2 2 DISP
  R4 'R3' STO R3 3 DISP
  R5 'R4' STO R4 4 DISP
  R6 'R5' STO R5 5 DISP
  R7 'R6' STO R6 6 DISP
  7 "" GS FLS
>>

TEN
<<
CLLCD
1 7 FOR C C "" GS FLS NEXT
DO SCROLL UNTIL R1 R2 SAME END
>>