使用epm1270t144c5开发板， 自动售货机 ⚫ 机器只接受 1 元硬币和 5 角硬币。 ⚫ 机器共提供 4 种货物，价格分别为 2 元、2 元、1.5 元、1.5 元（可通过调整代码改变每 种货物的单价）。 ⚫ 顾客选择货物后，显示货物数量。顾客确认数量后，机器根据货物数量判断是否购买成 功 ⚫ 购买成功点阵显示屏笑脸，购买失败显示哭脸 ⚫ 增加串口功能，pc 端的串口调试助手可以显示选择的商品信息，价格，数量。并且显 示购买成功与否的代码

这是一个比较复杂的项目，需要涉及硬件和编程。以下是大致的代码框架，需要根据具体的硬件和功能进行修改和完善：

#include <stdio.h>
#include <stdlib.h>
#include <string.h>

// 定义货物信息结构体
struct Product {
    char *name; // 名称
    float price; // 单价
    int quantity; // 数量
};

// 定义货币信息结构体
struct Currency {
    int one_yuan; // 1元硬币数量
    int five_jiao; // 5角硬币数量
    float total; // 总额
};

// 初始化货物信息
void init_products(struct Product products[]) {
    products[0].name = "Product1";
    products[0].price = 2.0;
    products[0].quantity = 10;
    products[1].name = "Product2";
    products[1].price = 2.0;
    products[1].quantity = 10;
    products[2].name = "Product3";
    products[2].price = 1.5;
    products[2].quantity = 10;
    products[3].name = "Product4";
    products[3].price = 1.5;
    products[3].quantity = 10;
}

// 显示货物信息
void show_products(struct Product products[]) {
    printf("Products:\n");
    for (int i = 0; i < 4; i++) {
        printf("%d. %s: %.2f yuan, %d pieces\n", i + 1, products[i].name, products[i].price, products[i].quantity);
    }
}

// 初始化货币信息
void init_currency(struct Currency *currency) {
    currency->one_yuan = 0;
    currency->five_jiao = 0;
    currency->total = 0;
}

// 显示货币信息
void show_currency(struct Currency *currency) {
    printf("Currency:\n");
    printf("1 yuan: %d pieces\n", currency->one_yuan);
    printf("5 jiao: %d pieces\n", currency->five_jiao);
    printf("Total: %.2f yuan\n", currency->total);
}

// 插入硬币
void insert_coin(struct Currency *currency, int coin) {
    if (coin == 1) {
        currency->one_yuan++;
        currency->total += 1.0;
    } else if (coin == 5) {
        currency->five_jiao++;
        currency->total += 0.5;
    } else {
        printf("Invalid coin!\n");
    }
}

// 选择货物
int select_product(struct Product products[]) {
    int choice;
    printf("Select a product (1-4): ");
    scanf("%d", &choice);
    if (choice >= 1 && choice <= 4) {
        if (products[choice - 1].quantity > 0) {
            return choice - 1;
        } else {
            printf("No stock!\n");
            return -1;
        }
    } else {
        printf("Invalid choice!\n");
        return -1;
    }
}

// 选择数量
int select_quantity(struct Product *product) {
    int quantity;
    printf("Select quantity (1-%d): ", product->quantity);
    scanf("%d", &quantity);
    if (quantity >= 1 && quantity <= product->quantity) {
        return quantity;
    } else {
        printf("Invalid quantity!\n");
        return -1;
    }
}

// 购买货物
void buy_product(struct Product *product, struct Currency *currency) {
    int quantity = select_quantity(product);
    if (quantity > 0) {
        float cost = product->price * quantity;
        if (currency->total >= cost) {
            product->quantity -= quantity;
            currency->total -= cost;
            printf("Bought %d %s for %.2f yuan\n", quantity, product->name, cost);
        } else {
            printf("Not enough money!\n");
        }
    }
}

// 显示购买结果
void show_result(int success) {
    if (success) {
        printf(":)\n");
    } else {
        printf(":(\n");
    }
}

// 串口输出
void serial_output(struct Product *product, struct Currency *currency, int success) {
    char buffer[100];
    sprintf(buffer, "%s,%.2f,%d,%d,%d,%d,%.2f,%d\n", product->name, product->price, product->quantity, currency->one_yuan, currency->five_jiao, currency->total, success);
    // TODO: 串口输出
}

int main() {
    struct Product products[4];
    init_products(products);
    struct Currency currency;
    init_currency(&currency);
    show_products(products);
    show_currency(&currency);
    while (1) {
        int coin;
        printf("Insert coin (1 for 1 yuan, 5 for 5 jiao, 0 to finish): ");
        scanf("%d", &coin);
        if (coin == 0) {
            break;
        }
        insert_coin(&currency, coin);
        show_currency(&currency);
    }
    int index = select_product(products);
    if (index >= 0) {
        buy_product(&products[index], &currency);
        show_result(1);
    } else {
        show_result(0);
    }
    serial_output(&products[index], &currency, index >= 0);
    return 0;
}

以上代码中使用了结构体来存储货物信息和货币信息，分别定义了初始化、显示、插入硬币、选择货物、选择数量、购买货物、显示购买结果和串口输出等函数。在主函数中循环插入硬币，选择货物，购买货物，显示购买结果和进行串口输出。需要根据具体的硬件和功能进行修改和完善。