diff --git a/tests/gsm0502/gsm0502_test.ok b/tests/gsm0502/gsm0502_test.ok
new file mode 100644
index 0000000..89418d3
--- /dev/null
+++ b/tests/gsm0502/gsm0502_test.ok
@@ -0,0 +1,271 @@
+Testing gsm0502_fn_remap()
+TCH/F
+fn_end=1036987, fn_end%104=3, fn_begin=1036979, fn_begin%104=99
+fn_end=1036991, fn_end%104=7, fn_begin=1036984, fn_begin%104=0
+fn_end=1036995, fn_end%104=11, fn_begin=1036988, fn_begin%104=4
+fn_end=1037000, fn_end%104=16, fn_begin=1036992, fn_begin%104=8
+fn_end=1037004, fn_end%104=20, fn_begin=1036997, fn_begin%104=13
+fn_end=1037008, fn_end%104=24, fn_begin=1037001, fn_begin%104=17
+fn_end=1037013, fn_end%104=29, fn_begin=1037005, fn_begin%104=21
+fn_end=1037017, fn_end%104=33, fn_begin=1037010, fn_begin%104=26
+fn_end=1037021, fn_end%104=37, fn_begin=1037014, fn_begin%104=30
+fn_end=1037026, fn_end%104=42, fn_begin=1037018, fn_begin%104=34
+fn_end=1037030, fn_end%104=46, fn_begin=1037023, fn_begin%104=39
+fn_end=1037034, fn_end%104=50, fn_begin=1037027, fn_begin%104=43
+fn_end=1037039, fn_end%104=55, fn_begin=1037031, fn_begin%104=47
+fn_end=1037043, fn_end%104=59, fn_begin=1037036, fn_begin%104=52
+fn_end=1037047, fn_end%104=63, fn_begin=1037040, fn_begin%104=56
+fn_end=1037052, fn_end%104=68, fn_begin=1037044, fn_begin%104=60
+fn_end=1037056, fn_end%104=72, fn_begin=1037049, fn_begin%104=65
+fn_end=1037060, fn_end%104=76, fn_begin=1037053, fn_begin%104=69
+fn_end=1037065, fn_end%104=81, fn_begin=1037057, fn_begin%104=73
+fn_end=1037069, fn_end%104=85, fn_begin=1037062, fn_begin%104=78
+fn_end=1037073, fn_end%104=89, fn_begin=1037066, fn_begin%104=82
+fn_end=1037078, fn_end%104=94, fn_begin=1037070, fn_begin%104=86
+fn_end=1037082, fn_end%104=98, fn_begin=1037075, fn_begin%104=91
+fn_end=1037086, fn_end%104=102, fn_begin=1037079, fn_begin%104=95
+fn_end=1037091, fn_end%104=3, fn_begin=1037083, fn_begin%104=99
+fn_end=1037095, fn_end%104=7, fn_begin=1037088, fn_begin%104=0
+fn_end=1037099, fn_end%104=11, fn_begin=1037092, fn_begin%104=4
+fn_end=1037104, fn_end%104=16, fn_begin=1037096, fn_begin%104=8
+fn_end=1037108, fn_end%104=20, fn_begin=1037101, fn_begin%104=13
+fn_end=1037112, fn_end%104=24, fn_begin=1037105, fn_begin%104=17
+fn_end=1037117, fn_end%104=29, fn_begin=1037109, fn_begin%104=21
+fn_end=1037121, fn_end%104=33, fn_begin=1037114, fn_begin%104=26
+fn_end=1037125, fn_end%104=37, fn_begin=1037118, fn_begin%104=30
+fn_end=1037130, fn_end%104=42, fn_begin=1037122, fn_begin%104=34
+fn_end=1037134, fn_end%104=46, fn_begin=1037127, fn_begin%104=39
+fn_end=1037138, fn_end%104=50, fn_begin=1037131, fn_begin%104=43
+fn_end=1037143, fn_end%104=55, fn_begin=1037135, fn_begin%104=47
+fn_end=1037147, fn_end%104=59, fn_begin=1037140, fn_begin%104=52
+fn_end=1037151, fn_end%104=63, fn_begin=1037144, fn_begin%104=56
+fn_end=1037156, fn_end%104=68, fn_begin=1037148, fn_begin%104=60
+fn_end=1037160, fn_end%104=72, fn_begin=1037153, fn_begin%104=65
+fn_end=1037164, fn_end%104=76, fn_begin=1037157, fn_begin%104=69
+fn_end=1037169, fn_end%104=81, fn_begin=1037161, fn_begin%104=73
+fn_end=1037173, fn_end%104=85, fn_begin=1037166, fn_begin%104=78
+fn_end=1037177, fn_end%104=89, fn_begin=1037170, fn_begin%104=82
+fn_end=1037182, fn_end%104=94, fn_begin=1037174, fn_begin%104=86
+fn_end=1037186, fn_end%104=98, fn_begin=1037179, fn_begin%104=91
+fn_end=1037190, fn_end%104=102, fn_begin=1037183, fn_begin%104=95
+fn_end=1037195, fn_end%104=3, fn_begin=1037187, fn_begin%104=99
+fn_end=1037199, fn_end%104=7, fn_begin=1037192, fn_begin%104=0
+fn_end=1037203, fn_end%104=11, fn_begin=1037196, fn_begin%104=4
+fn_end=1037208, fn_end%104=16, fn_begin=1037200, fn_begin%104=8
+fn_end=1037212, fn_end%104=20, fn_begin=1037205, fn_begin%104=13
+fn_end=1037216, fn_end%104=24, fn_begin=1037209, fn_begin%104=17
+fn_end=1037221, fn_end%104=29, fn_begin=1037213, fn_begin%104=21
+fn_end=1037225, fn_end%104=33, fn_begin=1037218, fn_begin%104=26
+fn_end=1037229, fn_end%104=37, fn_begin=1037222, fn_begin%104=30
+fn_end=1037234, fn_end%104=42, fn_begin=1037226, fn_begin%104=34
+fn_end=1037238, fn_end%104=46, fn_begin=1037231, fn_begin%104=39
+fn_end=1037242, fn_end%104=50, fn_begin=1037235, fn_begin%104=43
+fn_end=1037247, fn_end%104=55, fn_begin=1037239, fn_begin%104=47
+fn_end=1037251, fn_end%104=59, fn_begin=1037244, fn_begin%104=52
+fn_end=1037255, fn_end%104=63, fn_begin=1037248, fn_begin%104=56
+fn_end=1037260, fn_end%104=68, fn_begin=1037252, fn_begin%104=60
+fn_end=1037264, fn_end%104=72, fn_begin=1037257, fn_begin%104=65
+fn_end=1037268, fn_end%104=76, fn_begin=1037261, fn_begin%104=69
+fn_end=1037273, fn_end%104=81, fn_begin=1037265, fn_begin%104=73
+fn_end=1037277, fn_end%104=85, fn_begin=1037270, fn_begin%104=78
+fn_end=1037281, fn_end%104=89, fn_begin=1037274, fn_begin%104=82
+fn_end=1037286, fn_end%104=94, fn_begin=1037278, fn_begin%104=86
+fn_end=1037290, fn_end%104=98, fn_begin=1037283, fn_begin%104=91
+fn_end=1037294, fn_end%104=102, fn_begin=1037287, fn_begin%104=95
+
+TCH/H0
+fn_end=1175826, fn_end%104=2, fn_begin=1175819, fn_begin%104=99
+fn_end=1175830, fn_end%104=6, fn_begin=1175824, fn_begin%104=0
+fn_end=1175834, fn_end%104=10, fn_begin=1175828, fn_begin%104=4
+fn_end=1175839, fn_end%104=15, fn_begin=1175832, fn_begin%104=8
+fn_end=1175843, fn_end%104=19, fn_begin=1175837, fn_begin%104=13
+fn_end=1175847, fn_end%104=23, fn_begin=1175841, fn_begin%104=17
+fn_end=1175852, fn_end%104=28, fn_begin=1175845, fn_begin%104=21
+fn_end=1175856, fn_end%104=32, fn_begin=1175850, fn_begin%104=26
+fn_end=1175860, fn_end%104=36, fn_begin=1175854, fn_begin%104=30
+fn_end=1175865, fn_end%104=41, fn_begin=1175858, fn_begin%104=34
+fn_end=1175869, fn_end%104=45, fn_begin=1175863, fn_begin%104=39
+fn_end=1175873, fn_end%104=49, fn_begin=1175867, fn_begin%104=43
+fn_end=1175878, fn_end%104=54, fn_begin=1175871, fn_begin%104=47
+fn_end=1175882, fn_end%104=58, fn_begin=1175876, fn_begin%104=52
+fn_end=1175886, fn_end%104=62, fn_begin=1175880, fn_begin%104=56
+fn_end=1175891, fn_end%104=67, fn_begin=1175884, fn_begin%104=60
+fn_end=1175895, fn_end%104=71, fn_begin=1175889, fn_begin%104=65
+fn_end=1175899, fn_end%104=75, fn_begin=1175893, fn_begin%104=69
+fn_end=1175904, fn_end%104=80, fn_begin=1175897, fn_begin%104=73
+fn_end=1175908, fn_end%104=84, fn_begin=1175902, fn_begin%104=78
+fn_end=1175912, fn_end%104=88, fn_begin=1175906, fn_begin%104=82
+fn_end=1175917, fn_end%104=93, fn_begin=1175910, fn_begin%104=86
+fn_end=1175921, fn_end%104=97, fn_begin=1175915, fn_begin%104=91
+fn_end=1175925, fn_end%104=101, fn_begin=1175919, fn_begin%104=95
+fn_end=1175930, fn_end%104=2, fn_begin=1175923, fn_begin%104=99
+fn_end=1175934, fn_end%104=6, fn_begin=1175928, fn_begin%104=0
+fn_end=1175938, fn_end%104=10, fn_begin=1175932, fn_begin%104=4
+fn_end=1175943, fn_end%104=15, fn_begin=1175936, fn_begin%104=8
+fn_end=1175947, fn_end%104=19, fn_begin=1175941, fn_begin%104=13
+fn_end=1175951, fn_end%104=23, fn_begin=1175945, fn_begin%104=17
+fn_end=1175956, fn_end%104=28, fn_begin=1175949, fn_begin%104=21
+fn_end=1175960, fn_end%104=32, fn_begin=1175954, fn_begin%104=26
+fn_end=1175964, fn_end%104=36, fn_begin=1175958, fn_begin%104=30
+fn_end=1175969, fn_end%104=41, fn_begin=1175962, fn_begin%104=34
+fn_end=1175973, fn_end%104=45, fn_begin=1175967, fn_begin%104=39
+fn_end=1175977, fn_end%104=49, fn_begin=1175971, fn_begin%104=43
+fn_end=1175982, fn_end%104=54, fn_begin=1175975, fn_begin%104=47
+fn_end=1175986, fn_end%104=58, fn_begin=1175980, fn_begin%104=52
+fn_end=1175990, fn_end%104=62, fn_begin=1175984, fn_begin%104=56
+fn_end=1175995, fn_end%104=67, fn_begin=1175988, fn_begin%104=60
+fn_end=1175999, fn_end%104=71, fn_begin=1175993, fn_begin%104=65
+fn_end=1176003, fn_end%104=75, fn_begin=1175997, fn_begin%104=69
+fn_end=1176008, fn_end%104=80, fn_begin=1176001, fn_begin%104=73
+fn_end=1176012, fn_end%104=84, fn_begin=1176006, fn_begin%104=78
+fn_end=1176016, fn_end%104=88, fn_begin=1176010, fn_begin%104=82
+fn_end=1176021, fn_end%104=93, fn_begin=1176014, fn_begin%104=86
+fn_end=1176025, fn_end%104=97, fn_begin=1176019, fn_begin%104=91
+fn_end=1176029, fn_end%104=101, fn_begin=1176023, fn_begin%104=95
+fn_end=1176034, fn_end%104=2, fn_begin=1176027, fn_begin%104=99
+fn_end=1176038, fn_end%104=6, fn_begin=1176032, fn_begin%104=0
+fn_end=1176042, fn_end%104=10, fn_begin=1176036, fn_begin%104=4
+fn_end=1176047, fn_end%104=15, fn_begin=1176040, fn_begin%104=8
+fn_end=1176051, fn_end%104=19, fn_begin=1176045, fn_begin%104=13
+fn_end=1176055, fn_end%104=23, fn_begin=1176049, fn_begin%104=17
+fn_end=1176060, fn_end%104=28, fn_begin=1176053, fn_begin%104=21
+fn_end=1176064, fn_end%104=32, fn_begin=1176058, fn_begin%104=26
+fn_end=1176068, fn_end%104=36, fn_begin=1176062, fn_begin%104=30
+fn_end=1176073, fn_end%104=41, fn_begin=1176066, fn_begin%104=34
+fn_end=1176077, fn_end%104=45, fn_begin=1176071, fn_begin%104=39
+fn_end=1176081, fn_end%104=49, fn_begin=1176075, fn_begin%104=43
+fn_end=1176086, fn_end%104=54, fn_begin=1176079, fn_begin%104=47
+fn_end=1176090, fn_end%104=58, fn_begin=1176084, fn_begin%104=52
+fn_end=1176094, fn_end%104=62, fn_begin=1176088, fn_begin%104=56
+fn_end=1176099, fn_end%104=67, fn_begin=1176092, fn_begin%104=60
+fn_end=1176103, fn_end%104=71, fn_begin=1176097, fn_begin%104=65
+fn_end=1176107, fn_end%104=75, fn_begin=1176101, fn_begin%104=69
+fn_end=1176112, fn_end%104=80, fn_begin=1176105, fn_begin%104=73
+fn_end=1176116, fn_end%104=84, fn_begin=1176110, fn_begin%104=78
+fn_end=1176120, fn_end%104=88, fn_begin=1176114, fn_begin%104=82
+fn_end=1176125, fn_end%104=93, fn_begin=1176118, fn_begin%104=86
+fn_end=1176129, fn_end%104=97, fn_begin=1176123, fn_begin%104=91
+fn_end=1176133, fn_end%104=101, fn_begin=1176127, fn_begin%104=95
+
+TCH/H1
+fn_end=1175827, fn_end%104=3, fn_begin=1175820, fn_begin%104=100
+fn_end=1175831, fn_end%104=7, fn_begin=1175825, fn_begin%104=1
+fn_end=1175835, fn_end%104=11, fn_begin=1175829, fn_begin%104=5
+fn_end=1175840, fn_end%104=16, fn_begin=1175833, fn_begin%104=9
+fn_end=1175844, fn_end%104=20, fn_begin=1175838, fn_begin%104=14
+fn_end=1175848, fn_end%104=24, fn_begin=1175842, fn_begin%104=18
+fn_end=1175853, fn_end%104=29, fn_begin=1175846, fn_begin%104=22
+fn_end=1175857, fn_end%104=33, fn_begin=1175851, fn_begin%104=27
+fn_end=1175861, fn_end%104=37, fn_begin=1175855, fn_begin%104=31
+fn_end=1175866, fn_end%104=42, fn_begin=1175859, fn_begin%104=35
+fn_end=1175870, fn_end%104=46, fn_begin=1175864, fn_begin%104=40
+fn_end=1175874, fn_end%104=50, fn_begin=1175868, fn_begin%104=44
+fn_end=1175879, fn_end%104=55, fn_begin=1175872, fn_begin%104=48
+fn_end=1175883, fn_end%104=59, fn_begin=1175877, fn_begin%104=53
+fn_end=1175887, fn_end%104=63, fn_begin=1175881, fn_begin%104=57
+fn_end=1175892, fn_end%104=68, fn_begin=1175885, fn_begin%104=61
+fn_end=1175896, fn_end%104=72, fn_begin=1175890, fn_begin%104=66
+fn_end=1175900, fn_end%104=76, fn_begin=1175894, fn_begin%104=70
+fn_end=1175905, fn_end%104=81, fn_begin=1175898, fn_begin%104=74
+fn_end=1175909, fn_end%104=85, fn_begin=1175903, fn_begin%104=79
+fn_end=1175913, fn_end%104=89, fn_begin=1175907, fn_begin%104=83
+fn_end=1175918, fn_end%104=94, fn_begin=1175911, fn_begin%104=87
+fn_end=1175922, fn_end%104=98, fn_begin=1175916, fn_begin%104=92
+fn_end=1175926, fn_end%104=102, fn_begin=1175920, fn_begin%104=96
+fn_end=1175931, fn_end%104=3, fn_begin=1175924, fn_begin%104=100
+fn_end=1175935, fn_end%104=7, fn_begin=1175929, fn_begin%104=1
+fn_end=1175939, fn_end%104=11, fn_begin=1175933, fn_begin%104=5
+fn_end=1175944, fn_end%104=16, fn_begin=1175937, fn_begin%104=9
+fn_end=1175948, fn_end%104=20, fn_begin=1175942, fn_begin%104=14
+fn_end=1175952, fn_end%104=24, fn_begin=1175946, fn_begin%104=18
+fn_end=1175957, fn_end%104=29, fn_begin=1175950, fn_begin%104=22
+fn_end=1175961, fn_end%104=33, fn_begin=1175955, fn_begin%104=27
+fn_end=1175965, fn_end%104=37, fn_begin=1175959, fn_begin%104=31
+fn_end=1175970, fn_end%104=42, fn_begin=1175963, fn_begin%104=35
+fn_end=1175974, fn_end%104=46, fn_begin=1175968, fn_begin%104=40
+fn_end=1175978, fn_end%104=50, fn_begin=1175972, fn_begin%104=44
+fn_end=1175983, fn_end%104=55, fn_begin=1175976, fn_begin%104=48
+fn_end=1175987, fn_end%104=59, fn_begin=1175981, fn_begin%104=53
+fn_end=1175991, fn_end%104=63, fn_begin=1175985, fn_begin%104=57
+fn_end=1175996, fn_end%104=68, fn_begin=1175989, fn_begin%104=61
+fn_end=1176000, fn_end%104=72, fn_begin=1175994, fn_begin%104=66
+fn_end=1176004, fn_end%104=76, fn_begin=1175998, fn_begin%104=70
+fn_end=1176009, fn_end%104=81, fn_begin=1176002, fn_begin%104=74
+fn_end=1176013, fn_end%104=85, fn_begin=1176007, fn_begin%104=79
+fn_end=1176017, fn_end%104=89, fn_begin=1176011, fn_begin%104=83
+fn_end=1176022, fn_end%104=94, fn_begin=1176015, fn_begin%104=87
+fn_end=1176026, fn_end%104=98, fn_begin=1176020, fn_begin%104=92
+fn_end=1176030, fn_end%104=102, fn_begin=1176024, fn_begin%104=96
+fn_end=1176035, fn_end%104=3, fn_begin=1176028, fn_begin%104=100
+fn_end=1176039, fn_end%104=7, fn_begin=1176033, fn_begin%104=1
+fn_end=1176043, fn_end%104=11, fn_begin=1176037, fn_begin%104=5
+fn_end=1176048, fn_end%104=16, fn_begin=1176041, fn_begin%104=9
+fn_end=1176052, fn_end%104=20, fn_begin=1176046, fn_begin%104=14
+fn_end=1176056, fn_end%104=24, fn_begin=1176050, fn_begin%104=18
+fn_end=1176061, fn_end%104=29, fn_begin=1176054, fn_begin%104=22
+fn_end=1176065, fn_end%104=33, fn_begin=1176059, fn_begin%104=27
+fn_end=1176069, fn_end%104=37, fn_begin=1176063, fn_begin%104=31
+fn_end=1176074, fn_end%104=42, fn_begin=1176067, fn_begin%104=35
+fn_end=1176078, fn_end%104=46, fn_begin=1176072, fn_begin%104=40
+fn_end=1176082, fn_end%104=50, fn_begin=1176076, fn_begin%104=44
+fn_end=1176087, fn_end%104=55, fn_begin=1176080, fn_begin%104=48
+fn_end=1176091, fn_end%104=59, fn_begin=1176085, fn_begin%104=53
+fn_end=1176095, fn_end%104=63, fn_begin=1176089, fn_begin%104=57
+fn_end=1176100, fn_end%104=68, fn_begin=1176093, fn_begin%104=61
+fn_end=1176104, fn_end%104=72, fn_begin=1176098, fn_begin%104=66
+fn_end=1176108, fn_end%104=76, fn_begin=1176102, fn_begin%104=70
+fn_end=1176113, fn_end%104=81, fn_begin=1176106, fn_begin%104=74
+fn_end=1176117, fn_end%104=85, fn_begin=1176111, fn_begin%104=79
+fn_end=1176121, fn_end%104=89, fn_begin=1176115, fn_begin%104=83
+fn_end=1176126, fn_end%104=94, fn_begin=1176119, fn_begin%104=87
+fn_end=1176130, fn_end%104=98, fn_begin=1176124, fn_begin%104=92
+fn_end=1176134, fn_end%104=102, fn_begin=1176128, fn_begin%104=96
+
+FACCH/F
+fn_end=177275, fn_end%104=59, fn_begin=177268, fn_begin%104=52
+fn_end=177314, fn_end%104=98, fn_begin=177307, fn_begin%104=91
+fn_end=177336, fn_end%104=16, fn_begin=177328, fn_begin%104=8
+fn_end=177375, fn_end%104=55, fn_begin=177367, fn_begin%104=47
+fn_end=177396, fn_end%104=76, fn_begin=177389, fn_begin%104=69
+fn_end=177435, fn_end%104=11, fn_begin=177428, fn_begin%104=4
+fn_end=178328, fn_end%104=72, fn_begin=178321, fn_begin%104=65
+fn_end=178367, fn_end%104=7, fn_begin=178360, fn_begin%104=0
+fn_end=178393, fn_end%104=33, fn_begin=178386, fn_begin%104=26
+fn_end=180014, fn_end%104=94, fn_begin=180006, fn_begin%104=86
+fn_end=180053, fn_end%104=29, fn_begin=180045, fn_begin%104=21
+fn_end=180079, fn_end%104=55, fn_begin=180071, fn_begin%104=47
+fn_end=180113, fn_end%104=89, fn_begin=180106, fn_begin%104=82
+fn_end=180144, fn_end%104=16, fn_begin=180136, fn_begin%104=8
+fn_end=180183, fn_end%104=55, fn_begin=180175, fn_begin%104=47
+
+FACCH/H0
+fn_end=499956, fn_end%104=28, fn_begin=499945, fn_begin%104=17
+fn_end=499999, fn_end%104=71, fn_begin=499988, fn_begin%104=60
+fn_end=500034, fn_end%104=2, fn_begin=500023, fn_begin%104=95
+fn_end=500077, fn_end%104=45, fn_begin=500066, fn_begin%104=34
+fn_end=500952, fn_end%104=88, fn_begin=500942, fn_begin%104=78
+fn_end=501836, fn_end%104=36, fn_begin=501826, fn_begin%104=26
+fn_end=501880, fn_end%104=80, fn_begin=501869, fn_begin%104=69
+fn_end=502850, fn_end%104=10, fn_begin=502840, fn_begin%104=0
+fn_end=502894, fn_end%104=54, fn_begin=502883, fn_begin%104=43
+fn_end=502937, fn_end%104=97, fn_begin=502926, fn_begin%104=86
+fn_end=503006, fn_end%104=62, fn_begin=502996, fn_begin%104=52
+fn_end=503050, fn_end%104=2, fn_begin=503039, fn_begin%104=95
+
+FACCH/H1
+fn_end=500728, fn_end%104=72, fn_begin=500717, fn_begin%104=61
+fn_end=500771, fn_end%104=11, fn_begin=500761, fn_begin%104=1
+fn_end=500797, fn_end%104=37, fn_begin=500787, fn_begin%104=27
+fn_end=500841, fn_end%104=81, fn_begin=500830, fn_begin%104=70
+fn_end=500875, fn_end%104=11, fn_begin=500865, fn_begin%104=1
+fn_end=500919, fn_end%104=55, fn_begin=500908, fn_begin%104=44
+fn_end=501751, fn_end%104=55, fn_begin=501740, fn_begin%104=44
+fn_end=501794, fn_end%104=98, fn_begin=501783, fn_begin%104=87
+fn_end=501837, fn_end%104=37, fn_begin=501827, fn_begin%104=27
+fn_end=502782, fn_end%104=46, fn_begin=502771, fn_begin%104=35
+fn_end=502825, fn_end%104=89, fn_begin=502815, fn_begin%104=79
+fn_end=502869, fn_end%104=29, fn_begin=502858, fn_begin%104=18
+fn_end=502903, fn_end%104=63, fn_begin=502893, fn_begin%104=53
+fn_end=502955, fn_end%104=11, fn_begin=502945, fn_begin%104=1
+fn_end=502999, fn_end%104=55, fn_begin=502988, fn_begin%104=44
+