Brother HL-1260 service manual Display Circuit

3.DISPLAY CIRCUIT

3.1 Outline

The control panel of this printer has four LED lamps, one LCD display, and eight switches. The control panel is connected to the Main PCB and its functions are as follows:

(1)The LCD shows the printer status and error message in alpha-numeric characters.

(2)The LED lamps indicate the operating conditions of the printer.

(3)The printing mode and LCD brightness can be changed by switches.

LED1

LED2

LCD

SW8

SW7

SW6

SW5

SW4

SW3

SW2

SW1

LED3

LED4

PAD4-PAD7

LED2 (READY)

LED3 (DATA)

LED4 (ALARM)

LCDE, LCDRS

LED1 (ONLINE)

SW8 (SEL)

SW7 (MODE)

SW6 (FONT)

SW5 (FORM FEED)

SW4 (SET)

SW3 (CONTINUE)

SW2 (DOWN)

SW1 (UP)

Main PCB

Figure 3.8 Display Circuit

3.2 Operation

Indicators on the control panel (LED lamps and LCD) are controlled by the video controller circuit.

All the switch signals are input to the video controller circuit.

Signals Descriptions:

LED1 - LED4	On-off control for the respective LED lamps.
	Illuminating when Low and extinguished when High.
PAD4 - PAD7	LCD control signal.
LCDRS	A signal to distinguish PAD4 - PAD7 into command and data.
LCDE	A signal to start the operation.
SW1 - SW8	Input signals from the switches.
	Going Low when each switch is pressed.

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