Advertisement
Flow description:
<82C14>：Setup data: 14h. 2Ch[4] = 1 enables 12.5k LPF. 2Ch[2] = 1 enables 300Hz
HPF.
In-band Signal Level Adjustment Function
The output modulation differs between different system applications. The device provides
multi-level modulating settings for different paths and also provides a mixer. The
modulation diagram and description are as follows:
VR1：The internal audio generator modulation level select (I/O CMD-11h[4-2 : b'010]),
256 levels, Default：00h.
VR2：Sub-tone modulation level select, 256 levels, Default：00h.
VR3：Mixer modulation option/setting. When VR3=0, it means no MIX function, 256
levels, Default：00h.
VR4：The MOD (pin) in-band output modulation select, 1024 levels, Default：3FFh.
VR5：The SMOD (pin) sub-tone output modulation select, 1024 levels, Default：3FFh.
The MOD output depends on the VR1 setting (if a tone generator is used), VR4 and the
system operating voltage. The SMOD output depends on VR2, VR5 and the system
operating voltage. However, there may be some distortion in the actual output (RC
filter...etc.) For example, in a 3 V system, MOD Output(max) ~= 2780mv，SMOD
Output(max) ~= 1920mv due to the default value of the audio processor. Users must
enable or change the modulation level of the path for their application.
HT98R068 Two-way Radio MCU
Modulation Pth Block Diagram
24
Advertisement
