【从0到1搭建LoRa物联网】7、国产LoRa终端ASR6505驱动段式LCD例程

系列文章：
【从0到1搭建LoRa物联网】1、LoRa物联网的架构
【从0到1搭建LoRa物联网】2、终端设备开发方式
【从0到1搭建LoRa物联网】3、国产LoRa终端ASR6505软硬件
【从0到1搭建LoRa物联网】4、国产LoRa终端ASR6505普通GPIO
【从0到1搭建LoRa物联网】5、国产LoRa终端ASR6505驱动DHT11
【从0到1搭建LoRa物联网】6、国产LoRa终端ASR6505 I2C接口

1、前言

STM8L15x有LCD控制器外设，不需要使用额外的芯片，可以直接驱动段式LCD。ASR6505预留了最大4COM、18SEG的LCD接口，即就是开发板最右边的接口。

2、LCD驱动电源

软件来选择VLCD的电源，如果使用内部供电，则需要VLCD引脚断开（P3跳线帽断开），反之闭合。

3、ASR6505 LCD相关引脚与STM8L对应关系

ASR6505 LCD相关引脚与STM8L对应关系如下：

ASR6505 Pin Name	STM8 Pin Name
SEG17	PG7(SEG35)
SEG16	PD6(SEG20)
SEG15	PD5(SEG19)
SEG14	PD4(SEG18)
SEG13	PF7(SEG43)
SEG12	PF6(SEG42)
SEG11	PF5(SEG41)
SEG10	PF4(SEG40)
SEG9	PB7(SEG17)
SEG8	PB6(SEG16)
SEG7	PB5(SEG15)
SEG6	PB4(SEG14)
SEG5	PD3(SEG9)
SEG4	PD2(SEG8)
SEG3	PD0(SEG7)
SEG2	PE5(SEG6)
SEG1	PE4(SEG5)
SEG0	PE3(SEG4)
COM3	PD1(COM3)
COM2	PA6(COM2)
COM1	PA5(COM1)
COM0	PA4(COM0)

4、段式LCD

5、LCD参数

参数：Bias偏置电压是1/3，Duty占空比是1/4，需要4个COM口和12个SEG口。
连接：ASR6505对应连接LCD也是用COM0-COM3（对应LCD的Pin1-Pin4），SEG0-SEG12（对应LCD的Pin5-Pin16）。

6、STM8L的LCD的SEG引脚使能

由上面的图可知，连接LCD需要ASR6505的SEG0-SEG11，对应到STM8L上面就是SEG4-SEG9、SEG14-SEG17、SEG40-SEG41，共12个SEG口,在下图在用红圈标了出来。

7、段式LCD点亮分析

查看LCD规格书可知，点亮第一个“点”需要往对应的缓存（LCD_RAM）写1，下面是STM8L的LCD_RAM表和段式LCD的映射表：

8、代码实现

void LCD_PeriphInit(void)
{CLK_PeripheralClockConfig(CLK_Peripheral_LCD, ENABLE);//LCD驱动时钟门控使能LCD_DeInit( );//LCD相关寄存器恢复初值LCD_Init(LCD_Prescaler_4, LCD_Divider_16,//LCD驱动初始化，LCD刷新频率LCD_Duty_1_4, LCD_Bias_1_3,//1/4DUTY 1/3BIAS，看屏幕参数LCD_VoltageSource_Internal);//选择LCD驱动电源，外部或内部LCD_PortMaskConfig(LCD_PortMaskRegister_0, 0xF0); //SEG4-7LCD_PortMaskConfig(LCD_PortMaskRegister_1, 0xC3); //SEG8-9,SEG14-15LCD_PortMaskConfig(LCD_PortMaskRegister_2, 0x3F); //SEG16-21LCD_PortMaskConfig(LCD_PortMaskRegister_3, 0x00); //NONELCD_PortMaskConfig(LCD_PortMaskRegister_4, 0x00); //MONELCD_PortMaskConfig(LCD_PortMaskRegister_5, 0x0F); //SEG40-43LCD_ContrastConfig(LCD_Contrast_3V3);//配置对比度LCD_DeadTimeConfig(LCD_DeadTime_0);  //设置死区时间LCD_PulseOnDurationConfig(LCD_PulseOnDuration_5);// 配置LCD脉冲持续时间LCD_HighDriveCmd(ENABLE);LCD_Cmd(ENABLE);
}void LCD_Display(void)
{    //对显示缓冲区操作，要结合液晶说明书 static uint8_t i=0;   i++;if(i>=255){i=0;}if(i%2){LCD_WriteRAM(LCD_RAMRegister_0, 0x30|0xC0|0x03|0x00|0x00|0x00);  LCD_WriteRAM(LCD_RAMRegister_1, 0x00|0x00|0x03|0xC0|0x00|0x00);  LCD_WriteRAM(LCD_RAMRegister_2, 0x00|0x00|0x00|0x00|0x03|0x00);  LCD_WriteRAM(LCD_RAMRegister_4, 0x03|0x0C|0x30|0x00|0x00|0x00);  LCD_WriteRAM(LCD_RAMRegister_5, 0x00|0x00|0x00|0x0C|0x30|0x00);  LCD_WriteRAM(LCD_RAMRegister_7, 0x30|0xC0|0x00|0x00|0x00|0x00);  LCD_WriteRAM(LCD_RAMRegister_8, 0x00|0x00|0x03|0xC0|0x00|0x00);  LCD_WriteRAM(LCD_RAMRegister_9, 0x00|0x00|0x00|0x00|0x03|0x00);  LCD_WriteRAM(LCD_RAMRegister_11,0x03|0x0c|0x30|0x00|0x00|0x00);  LCD_WriteRAM(LCD_RAMRegister_12,0x00|0x00|0x00|0x0C|0x30|0x00);  LCD_WriteRAM(LCD_RAMRegister_15,0x00|0x00|0x00|0x00|0x00|0x30);  LCD_WriteRAM(LCD_RAMRegister_17,0x00|0x00|0x00|0x00|0x00|0x30);  LCD_WriteRAM(LCD_RAMRegister_19,0x00|0x00|0x00|0x00|0x00|0x30);  LCD_WriteRAM(LCD_RAMRegister_21,0x00|0x00|0x00|0x00|0x00|0x30);  }else{LCD_WriteRAM(LCD_RAMRegister_0, 0x20|0xC0|0x03|0x00|0x00|0x00);  LCD_WriteRAM(LCD_RAMRegister_1, 0x00|0x00|0x03|0x80|0x00|0x00);   LCD_WriteRAM(LCD_RAMRegister_2, 0x00|0x00|0x00|0x00|0x01|0x00);   LCD_WriteRAM(LCD_RAMRegister_4, 0x00|0x08|0x20|0x00|0x00|0x00);   LCD_WriteRAM(LCD_RAMRegister_5, 0x00|0x00|0x00|0x0C|0x30|0x00);  LCD_WriteRAM(LCD_RAMRegister_7, 0x20|0x40|0x00|0x00|0x00|0x00);   LCD_WriteRAM(LCD_RAMRegister_8, 0x00|0x00|0x02|0x80|0x00|0x00);  LCD_WriteRAM(LCD_RAMRegister_9, 0x00|0x00|0x00|0x00|0x02|0x00);  LCD_WriteRAM(LCD_RAMRegister_11,0x00|0x08|0x20|0x00|0x00|0x00); LCD_WriteRAM(LCD_RAMRegister_12,0x00|0x00|0x00|0x00|0x20|0x00);  LCD_WriteRAM(LCD_RAMRegister_15,0x00|0x00|0x00|0x00|0x00|0x10);  LCD_WriteRAM(LCD_RAMRegister_17,0x00|0x00|0x00|0x00|0x00|0x30); LCD_WriteRAM(LCD_RAMRegister_19,0x00|0x00|0x00|0x00|0x00|0x30);  LCD_WriteRAM(LCD_RAMRegister_21,0x00|0x00|0x00|0x00|0x00|0x30);  }
}

9、实验现象

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