Huawei ETS2000 Series Maintenance Manual page 10

Figure1-10
Hands-free interface circuit
Possible faults of the hands-free channel: There is no ringing. Then check whether
or not U101 is damaged.
3，LCD unit
In the ETS2000 series FWTs, LCD is a peripheral component. If it is broken, it can
be replaced directly. Then you had better be clear about the function of LCD to
choose proper LCD codes. If the dot matrix has no back facet, choose 23040026.
If the dot matrix has olivine back facet, choose 23040028.
LCD (Here, we takes dot matrix LCD as the example) connects the system via 2
10PIN conductor layouts. Interfaces are shown in Table 1-1.
See Figure 1-11 for hardware interfaces:
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