Hardware And Software Guide - Ebyte E78-900M22S1A User Manual

Chengdu Ebyte Electronic Technology Co., Ltd.
39 LCD-SEG0
40 GND
41 LCD-SEG3
42 LCD-COM3
43 LCD-SEG4
44 LCD-SEG5
45 UART0-RX
46 UART0-TX
47 LCD-SEG6
48 LCD-SEG7
49 LCD-SEG8
50 LCD-SEG9
51 VCC
52 GND
For more information about module pin definition, software driver and communication protocol, please see

4 Hardware and Software Guide

4.1 Hardware Design
It is recommended to use a DC stabilized power supply to supply power to the module, and the power ripple

coefficient should be as small as possible, and the module should be reliably grounded;
Please pay attention to the correct connection of the positive and negative poles of the power supply. Reverse

connection may cause permanent damage to the module;
Please check the power supply to ensure that it is within the recommended power supply voltage. If it exceeds the

maximum value, it will cause permanent damage to the module;
Please check the stability of the power supply, and the voltage should not fluctuate greatly and frequently;

When designing the power supply circuit for the module, it is often recommended to reserve more than 30% of the

margin, and the whole machine is conducive to long-term stable operation;
The module should be as far away as possible from the power supply, transformer, high-frequency wiring and other

parts with large electromagnetic interference;
High-frequency digital wiring, high-frequency analog wiring, and power wiring must avoid the bottom of the

module. If it is necessary to pass under the module, assume that the module is soldered to the Top Layer, and the top
layer of the contact part of the module is covered with copper (all copper And well grounded), it must be close to
the digital part of the module and routed in the Bottom Layer;
Assuming that the module is soldered or placed on the Top Layer, it is also wrong to randomly route the wires on

the Bottom Layer or other layers, which will affect the stray and receiving sensitivity of the module to varying
degrees;
Assuming that there are devices with large electromagnetic interference around the module, it will greatly affect the

performance of the module. According to the intensity of the interference, it is recommended to stay away from the
module. If the situation permits, proper isolation and shielding can be done;
Assuming that there are traces with large electromagnetic interference around the module (high-frequency digital,

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Input/Output MCU GPIO
- Ground wire, connected to the power reference ground
Input/Output MCU GPIO
Input/Output MCU GPIO
Input/Output MCU GPIO
Input/Output MCU GPIO
Input UART0-RX pin
Output UART0-TX pin
Input/Output MCU GPIO
Input/Output MCU GPIO
Input/Output MCU GPIO
Input/Output MCU GPIO
- Power supply, range 1.8V~3.7V (recommend to add ceramic filter capacitor)
- Ground wire, connected to the power reference ground
E78-900M22S1A User Manual
ASR6505 Datasheet
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