Avery Berkel CX20 SERIES, Руководство по обслуживанию

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11 — Main PCB
11–3 CX20/CX30/CX34 Service Manual
11.1 Description
The main PCB carries all the circuitry required to scan and operate the keyboard
and displays, to perform calculations and to drive the printer. For a general
description of the function, refer to Section 2.
The main PCB carries a smaller PCB, the analogue–to–digital converter (A/D).
The A/D PCB converts the analogue signals received from the transducer and
converts it into digital form for use by the main PCB.
Electrical connectors on the main PCB are provided to connect with peripheral
devices (such as displays, printers, keyboard, cash drawer, and others). The
peripherals connected to the electrical connectors are application–specific and
some connectors will be unused in certain applications.
The main PCB has many optional features to make it suitable for a wide variety
of configurations and to provide various levels of operating power. Some of
these features are enabled by firmware (EPROM and ASIC) and some by
hardware changes (the setting of links and DIL switches). The following
information should be used for reference:
Configuration data is identified in Section 6.
PCB mounted connectors and their functions are identified in Figure 11.1
and Table 11.1.
DIL switches and their functions are identified in Figure 11.2 and
Table 11.3.
Links and their functions are identified in Figure 11.3 and Table 11.4.
Integrated circuits and their functions are identified in Figure 11.4.