Application Information ......
N = int (Frequency x Measurement Period)
Measurement Period
= 39.47ms for Low Band
= 13.16ms for High Band
(300Hz to 660Hz)
(900Hz to 2150Hz)
Note: For input frequencies of between 661Hz and 899Hz the FX613 will give no reliable output.
Bit 5
Output
First
Bits
0 to 4
Band Bit (5)
MSB (4)
(3)
(2)
(1)
LSB (0)
HI-“1”/LO-“0”
Bits 0 to 4 represent the measured frequency in the selected band
=
N
When a ‘correct’ decode has been allowed and an interrupt generated, a 6-bit data word will be presented at the
Serial Output Port. This 6-bit word indicates the input frequency's band and value as described below.
As an example, the following binary-word presented at the Serial Output Port (1 1 0 1 1 0) will indicate a
frequency in the HI Band of between 1680Hz and 1740Hz (Bit-5 = “1” = HI, ‘N’ = 22).
LO Band
HI Band
N
B5 B4 B3 B2 B1 B0
LO Band
HI Band
N
B5 B4 B3 B2 B1 B0
280
285
290
295
300
305
310
315
320
325
330
335
340
345
350
355
360
365
370
375
380
385
390
395
400
405
410
415
420
425
430
435
440
445
450
455
460
465
470
475
480
485
490
495
500
840
855
870
885
900
915
930
945
960
11
11
11
11
11
12
12
12
12
12
13
13
13
13
13
14
14
14
14
14
14
15
15
15
15
15
16
16
16
16
16
17
17
17
17
17
18
18
18
18
18
19
19
19
19
H/L
H/L
H/L
H/L
0
0
0
0
1
1
1
1
0
1
1
1
1
0
0
1
1
0
1
0
505
510
515
520
525
530
535
540
545
550
555
560
565
570
575
580
585
590
595
600
605
610
615
620
625
630
635
640
645
650
655
660
665
670
675
680
685
690
695
700
705
710
715
720
725
1515
1530
1545
1560
1575
1590
1605
1620
1635
1650
1665
1680
1695
1710
1725
1740
1755
1770
1785
1800
1815
1830
1845
1860
1875
1890
1905
1920
1935
1950
1965
1980
1995
2010
2025
2040
2055
2070
2085
2100
2115
2130
2145
2160
2175
19
20
20
20
20
20
21
21
21
21
21
22
22
22
22
22
23
23
23
23
23
24
24
24
24
24
25
25
25
25
25
26
26
26
26
26
27
27
27
27
27
28
28
28
28
H/L
H/L
1
1
0
0
0
1
1
0
1
0
H/L
H/L
H/L
H/L
H/L
H/L
H/L
H/L
1
1
1
1
1
1
1
1
0
0
0
1
1
1
1
1
1
1
1
0
0
0
0
1
0
1
1
0
0
1
1
0
1
0
1
0
1
0
1
0
975
990
1005
1020
1035
1050
1065
1080
1095
1110
1125
1140
1155
1170
1185
1200
1215
1230
1245
1260
1275
1290
1305
1320
1335
1350
1365
1380
1395
1410
1425
1440
1455
1470
1485
1500
H/L
H/L
H/L
H/L
H/L
0
1
1
1
1
1
0
0
0
0
1
0
0
0
0
1
0
0
1
1
1
0
1
0
1
Table 1 Decode Frequency Data
5
CMLMICRO [ CML MICROCIRCUITS ]
