AK2363 Datasheet, PDF (26/33 Pages) Asahi Kasei Microsystems – Radio Signaling LSI

ASAHI KASEI
[AK2363]
3) Setting the guard time
The tone duration accept time (t_REC), tone duration reject time (t_REJ), interdigit pause accept time (t_ID), and
interdigit pause reject time (t_DO) can be set to desired values by adjusting the guard time as shown below.
The guard time is set in registers GTPn and GTAn (n = 0 to 3).
Tone duration accept time (t_REC) = Tone present detection time (t_DP) + Guard time (t_GTP)
Tone duration accept time (t_REC) = Tone present detection time (t_DP) + Guard time (t_GTP) - Tone absent
detection time (t_DA)
Interdigit pause accept time (t_ID) = Tone absent detection time (t_DA) + Guard time (t_GTA)
Interdigit pause reject time (t_DO) = Tone absent detection time (t_DA) + Guard time (t_GTA) - Tone present
detection time (t_DP)
Guard time (t_GTP) setting range
Guard time (t_GTP) setting step
10ms to 134ms
9ms
Guard time (t_GTA) setting range
Guard time (t_GTA) setting step
19ms to 134ms
9ms
For the relationships between settings in registers GTPn and GTAn (n = 0 to 3) and guard time values, refer
to the tables given below.
The tables also show the relationships with the tone duration accept time (t_REC) and interdigit pause accept
time (t_ID).
Register GTPn (n = 0 to 3) vs. guard time t_GTP vs. tone duration accept time t_REC (AGC Disable)
t_DP (ms)
Min.
Typ.
Max.
5
11
16.8
GTP register
3
2
1
0
0
0
0
1
0
0
1
0
0
0
1
1
0
1
0
0
0
1
0
1
0
1
1
0
0
1
1
1
1
0
0
0
1
0
0
1
1
0
1
0
1
0
1
1
1
1
0
0
1
1
0
1
1
1
1
0
1
1
1
1
t_{GTP (ms)}
Typ.
10
19
28
37
46
54
63
72
81
90
99
108
117
126
134
t_REC(ms) = t_GTP + t_DP
Min.
Typ.
Max.
15
21
27
24
30
36
33
39
45
42
48
54
51
57
63
60
65
71
68
74
80
77
83
89
86
92
98
95
101
107
104
110
116
113
119
125
122
128
134
131
137
143
139
145
151
MS0583-E-01
- 26 -
2008/06