基于stm32f103c8t6的max7912驱动8×8点阵屏的测试代码

以下是基于stm32f103c8t6的max7912驱动8×8点阵屏的测试代码，供您参考：

#include "stm32f10x.h"

// 定义MAX7219各个寄存器地址
#define MAX7219_REG_NOOP        0x00
#define MAX7219_REG_DECODEMODE  0x09
#define MAX7219_REG_INTENSITY   0x0A
#define MAX7219_REG_SCANLIMIT   0x0B
#define MAX7219_REG_SHUTDOWN    0x0C
#define MAX7219_REG_DISPLAYTEST 0x0F

// 数码管编码表
const uint8_t DIGIT_CODE[] = {
  0x7E, 0x30, 0x6D, 0x79, 0x33, 0x5B, 0x5F, 0x70,
  0x7F, 0x7B, 0x77, 0x1F, 0x0D, 0x3D, 0x4F, 0x47
};

// MAX7219发送一个字节
void MAX7219_SendByte(uint8_t reg, uint8_t data) {
  GPIO_ResetBits(GPIOB, GPIO_Pin_12); // 使能
  SPI_I2S_SendData(SPI2, reg);
  while (SPI_I2S_GetFlagStatus(SPI2, SPI_I2S_FLAG_TXE) == RESET);
  SPI_I2S_SendData(SPI2, data);
  while (SPI_I2S_GetFlagStatus(SPI2, SPI_I2S_FLAG_TXE) == RESET);
  GPIO_SetBits(GPIOB, GPIO_Pin_12); // 禁止
}

// 初始化MAX7219
void MAX7219_Init() {
  MAX7219_SendByte(MAX7219_REG_SCANLIMIT, 0x07);       // 扫描位数，0-7都扫描
  MAX7219_SendByte(MAX7219_REG_DECODEMODE, 0x00);       // BCD编码模式
  MAX7219_SendByte(MAX7219_REG_DISPLAYTEST, 0x00);      // 关闭测试模式
  MAX7219_SendByte(MAX7219_REG_INTENSITY, 0x05);        // 亮度调节
  MAX7219_SendByte(MAX7219_REG_SHUTDOWN, 0x01);         // 开启正常工作模式
}

// 显示一个数字
void MAX7219_DisplayDigit(uint8_t digit, uint8_t value) {
  MAX7219_SendByte(digit + 1, DIGIT_CODE[value]);  // 发送数码管编码
}

int main() {
  // 初始化SPI2
  RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOB | RCC_APB2Periph_AFIO | RCC_APB2Periph_SPI1, ENABLE);
  GPIO_InitTypeDef GPIO_InitStructure;
  GPIO_InitStructure.GPIO_Pin = GPIO_Pin_13 | GPIO_Pin_15;
  GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;
  GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
  GPIO_Init(GPIOB, &GPIO_InitStructure);
  GPIO_InitStructure.GPIO_Pin = GPIO_Pin_12;
  GPIO_InitStructure.GPIO_Mode = GPIO_Mode_Out_PP;
  GPIO_Init(GPIOB, &GPIO_InitStructure);
  SPI_InitTypeDef SPI_InitStructure;
  SPI_InitStructure.SPI_Direction = SPI_Direction_2Lines_FullDuplex;
  SPI_InitStructure.SPI_Mode = SPI_Mode_Master;
  SPI_InitStructure.SPI_DataSize = SPI_DataSize_8b;
  SPI_InitStructure.SPI_CPOL = SPI_CPOL_Low;
  SPI_InitStructure.SPI_CPHA = SPI_CPHA_1Edge;
  SPI_InitStructure.SPI_NSS = SPI_NSS_Soft;
  SPI_InitStructure.SPI_BaudRatePrescaler = SPI_BaudRatePrescaler_16;
  SPI_InitStructure.SPI_FirstBit = SPI_FirstBit_MSB;
  SPI_InitStructure.SPI_CRCPolynomial = 7;
  SPI_Init(SPI2, &SPI_InitStructure);
  SPI_Cmd(SPI2, ENABLE);

  // 初始化MAX7219
  MAX7219_Init();

  // 显示数字0-9
  for (uint8_t i = 0; i < 10; i++) {
    MAX7219_DisplayDigit(7, i);
    for (volatile uint32_t j = 0; j < 1000000; j++) {}
  }

  while (1) {}
}

这段代码中，使用了STM32的SPI2接口来与MAX7219通信，将数字编码发送到MAX7219，显示在8×8点阵屏上。您可以根据具体硬件的接口定义进行修改。