10 REM FILE TEST
20 OPEN 1, 8, 4, "TESTFILE,SEQ,W"
30 IF ST <> 0 THEN PRINT "FILE ERROR"
40 IF ST = 0 THEN PRINT "FILE EXISTS"
50 CLOSE 1

NOT OUTPUT FILE

ERROR: #VKO8J1K1M6L56U5G7J8W9B5T9Z0NVO58