Brother MFC9100C Service Manual page 37

3.4 Control Panel PCB
The control panel PCB and the main PCB communicate with each other by serially transmitting
commands and data.
The control panel unit consists of a gate array, an LCD and LEDs, which are controlled by the gate
array according to commands issued from the control CPU on the main PCB.
The calendar clock is backed up by the backup circuit on the main PCB.
The panel FPC is a flexible keyboard PCB which integrates the key matrix having rubber keytops.
Control Panel PCB and its Related Circuit
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