Keywords: 12864 Monochrome Screen, 2.7-inch Display, Microcontroller, Hardware Connection, Software Debugging

JGS12864W2701-12864 Monochrome Screen Detailed Parameters

Model: JGS12864W2701

Product Type: STN Horizontal Screen

Resolution: 12864

Dimensions (L×W×H): 71.3×48.2×8.5

Viewing Area Size (VA): 65.5×38

Active Area Size (AA): 60.77×32.94

Display Size: 2.7

Viewing Angle: 6H

Backlight Type or Brightness: TBD

LED: TBD

Number of Connection Pins: 20

Interface Method: SPI+6800+8080

Special Note: Dot Matrix Screen

Operating Temperature: -20~70℃

Storage Temperature: -30~80℃

The JGS12864W2701-12864 monochrome screen is one of the commonly used displays for microcontrollers. The following is a detailed introduction to its usage:

I. Hardware Connection

Circuit Design

Design the PCB circuit diagram. The peripheral circuit is relatively simple, generally requiring only the addition of 9 non-polar 1μF/16V capacitors (note that the capacitor's voltage rating must be above 16V, as the internal boost voltage of the LCD may reach around 13.5V).

The VDD supply voltage for the LCD screen is typically 3.3V, with a voltage range of 2.7V~3.3V (software adjustment of contrast may be necessary if the voltage differs). If a 5V power supply is required, an AMS1117-3.3 voltage regulator can be used to step down the voltage to 3.3V.

Communication Method Selection

The 12864 LCD screen supports two communication methods: 8-bit parallel communication and SPI serial communication. For most products, SPI serial communication is a good choice as it reduces the number of I/O ports used, thereby lowering overall costs.

When using SPI serial communication, other unused pins should be connected to GND to improve display stability.

Wiring Considerations

Ensure that the wiring is correct, especially the connection of the contrast potentiometer pin VO. In practice, a 10K variable resistor is often used, with the sliding end connected to the VO pin, one fixed end connected to VCC, and the other end connected according to the actual hardware configuration (for the LCD12864 screen, refer to the marking of pin 18, as pin 18 is the negative voltage output).

If using a 51 microcontroller with the P0 port, a 10K pull-up resistor must be added; otherwise, even if the program is correct, the display may not work.

II. Software Debugging

Initialization Settings

Before software debugging, the LCD screen needs to be initialized, including setting the display start line, page address, column address, etc.

Write the corresponding initialization program based on the selected driver chip (such as KS0108 or ST7565).

Writing Display Programs

When writing display programs, the specific instructions and data format need to be determined based on the characteristics of the LCD screen and the chosen communication method.

For a 12864 LCD screen without a built-in font library, an external font array needs to be edited, and the font data must be written to the display RAM of the LCD screen.

When displaying Chinese characters, which are typically large (e.g., 16x16 dot matrix), they may need to be displayed across multiple pages. In this case, a corresponding paging display program needs to be written.

Debugging and Testing

After writing the display program, debugging and testing are required. First, observe whether pixel dots appear on the LCD screen and adjust the voltage of the VO pin to optimize the display effect.

Then, write simple test programs to verify whether the display function of the LCD screen is working properly. Test programs can include displaying simple graphics, text, etc.

III. Precautions

Avoid Damaging the LCD Screen

During use, avoid subjecting the LCD screen to excessive impact or vibration to prevent damage to its internal circuits or structure.

Additionally, avoid exposing the LCD screen to high or low temperatures for extended periods, as this may affect its lifespan and display quality.

Reasonable Contrast Settings

Contrast settings significantly impact the display effect. Adjust the contrast according to the lighting conditions of the actual usage environment to achieve the best display results.

Selecting the Appropriate Driver Chip

When selecting a driver chip, choose one that suits the characteristics of the LCD screen and the usage requirements. Different driver chips have different instruction sets and functional features, so selection should be based on specific circumstances.

The usage of the JGS12864W2701-12864 monochrome screen involves multiple aspects, including hardware connection, software debugging, and precautions. During use, carefully read the LCD screen's manual and the driver chip's specifications to ensure correct connection and usage of the LCD screen.

For the detailed specifications or documentation of the Jiaguan JGS12864W2701-12864 monochrome screen, please consult Engineer Dong.