Analog Unit - Panasonic KX-FM89BX Service Manual

This custom IC is used for the general FAX operations.
1. CPU:
This model uses a Z80 equivalent to the CPU operating at 8 MHz.
Most of the peripheral functions are performed by custom-
designed LSIs. Therefore, the CPU only works for processing the
results.
2. RTC:
Real Time Clock
3. DECODER:
Decodes the address.
4. ROM/RAM I/F:
Controls the SELECT signal of ROM or RAM and the bank
switching.
5. CIS I/F:
Controls the document reading.
6. IMAGE DATA RAM:
This memory is programmed into the ASIC and uses 8 KB for the
image processing. (See Fig. A.*)
7. THERMAL HEAD I/F:
Transmits the recorded data to the thermal head.
8. MOTOR I/F:
Controls the transmission motor which feeds the document.
Controls the receiving motor which feeds the recording paper.
9. OPERATION PANEL I/F:
Serial interface with Operation Panel.
10. I/O PORT:
I/O Port Interface.

11. ANALOG UNIT:

Electronic volume for the handset and the monitor.
Sends beep tones, etc.
Fig. A
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