diff --git a/serial_module.c b/serial_module.c index 5a37b79..15db5d2 100644 --- a/serial_module.c +++ b/serial_module.c @@ -15,24 +15,29 @@ #else #define FEC_SIZE 0 // 前向纠错冗余数据大小 #endif -#define FRAME_HEADER 0xAA55 // 帧头 -#define FRAME_TAIL 0x0D7E // 帧尾 -#define FRAME_SIZE (240) // 每帧大小 -#define HEADER_SIZE (4) // 帧头 + 帧序号 + 数据长度 -#define TAIL_SIZE (2) // 帧尾 -#define CHECKSUM_SIZE (4) // CRC32 校验和大小（4 字节） +#define FRAME_HEADER 0xAA55 // 帧头 +#define FRAME_TAIL 0x0D7E // 帧尾 +#define FRAME_SIZE (240) // 每帧大小 +#define HEADER_SIZE (4) // 帧头 + 帧序号 + 数据长度 +#define TAIL_SIZE (2) // 帧尾 +#define CHECKSUM_SIZE (4) // CRC32 校验和大小（4 字节） #define DATA_SIZE (FRAME_SIZE - HEADER_SIZE - CHECKSUM_SIZE - FEC_SIZE - TAIL_SIZE) // 数据段大小 -#define RING_BUFFER_SIZE (1024 * 10) // 环形缓冲区大小 - default 10KB -#define QUEUE_MAX_SIZE 1024 // 队列最大容量 +#define RING_BUFFER_SIZE (1024 * 10) // 环形缓冲区大小 - default 10KB +#define QUEUE_MAX_SIZE 1024 // 队列最大容量 // 全局变量 static by_serial_t serial_port; static by_ringbuf_t ring_buffer; static unsigned char send_buffer[FRAME_SIZE]; +static unsigned char recv_ack_data_buffer[DATA_SIZE]; static unsigned char frame_counter = 0; static unsigned char data_len = 0; -unsigned char output_data[8192]; +static unsigned char ack_flag = 0; +unsigned char output_data[8192]; // FIXME 有可能越界 static int output_len = 0; +static unsigned char ack_data_dummy[4] = {0x00, 0x00, 0x00, 0x00}; +static unsigned char ack_data[DATA_SIZE - 2] = {0}; +static int ack_data_len = 0; // 定义队列结构体 typedef struct @@ -46,10 +51,11 @@ static FrameData frame_queue[QUEUE_MAX_SIZE]; // 存储接收 static int queue_head = 0; // 队列头指针 static int queue_tail = 0; // 队列尾指针 static pthread_mutex_t queue_mutex = PTHREAD_MUTEX_INITIALIZER; // 保护队列的互斥锁 -static int stop_receiving = false; // 控制接收线程停止的标志 +static int stop_receiving = false; // 控制接收线程停止的标志 // 前向声明 void *receive_thread_func(void *arg); +int generate_response(unsigned char *data, int length, int ack); // 计算 CRC32 校验和 unsigned long calculate_crc32(const unsigned char *data, size_t length) @@ -93,7 +99,7 @@ int parse_frame(by_ringbuf_t *ringbuf, unsigned char *output_data, int *output_l { return -1; // 数据不足，无法解析 } - // 读取帧数据 + // 读取帧数据 by_ringbuf_pop(ringbuf, frame, HEADER_SIZE); int tail_pos = by_ringbuf_find(ringbuf, (unsigned char *)&tail, 2); if (tail_pos < FRAME_SIZE - HEADER_SIZE - TAIL_SIZE - 1) @@ -117,6 +123,23 @@ int parse_frame(by_ringbuf_t *ringbuf, unsigned char *output_data, int *output_l printf("CRC mismatch! Expected: %08X, Received: %08X\n", calculated_crc, received_crc); return -2; // CRC 校验失败，丢弃该帧，严重错误 } + + if (0xFF == seq) + { + // printf("Received ACK frame!\r\n"); + *output_len = 0; + if (0x1926 == *(unsigned short *)(data_segment)) + { + memcpy(recv_ack_data_buffer, data_segment + 2, valid_data_len - 2); + ack_data_len = valid_data_len - 2; + printf("Received ACK frame!\r\n"); + return 2; + } + + memset(recv_ack_data_buffer, 0, DATA_SIZE); + return 3; + } + // 将有效数据拼接到输出缓冲区 memcpy(&output_data[*output_len], data_segment, valid_data_len); *output_len += valid_data_len; @@ -141,6 +164,27 @@ void *receive_thread_func(void *arg) int parse_result = parse_frame(&ring_buffer, output_data, &output_len); if (parse_result == 1) { + int ack_data_len_t = 0; + + if (ack_data_len > DATA_SIZE - 2) + { + ack_data_len_t = DATA_SIZE - 2; + } + else + { + ack_data_len_t = ack_data_len; + } + + if (ack_data[0] == 0x00) + { + generate_response(ack_data_dummy, sizeof(ack_data_dummy), 1); + } + else + { + generate_response(ack_data, ack_data_len_t, 1); + // generate_response(ack_data_dummy, sizeof(ack_data_dummy), 1); + } + // 将解析后的数据放入队列 pthread_mutex_lock(&queue_mutex); if ((queue_tail + 1) % QUEUE_MAX_SIZE != queue_head) @@ -166,8 +210,21 @@ void *receive_thread_func(void *arg) } else if (parse_result == -2) { + // TODO 此处不能回应 NAK，必须等数据发完 output_len = 0; - break; // 数据不足或解析失败，退出循环 + break; // 严重错误，丢弃包 + } + else if (parse_result == 2) + { + ack_flag = 1; + printf("Received ACK frame!\r\n"); + break; + } + else if (parse_result == 3) + { + ack_flag = 2; + printf("Received NACK frame!\r\n"); + break; } } usleep(1000); // 避免占用过多 CPU @@ -175,6 +232,58 @@ void *receive_thread_func(void *arg) return NULL; } +int generate_response(unsigned char *data, int length, int ack) +{ + // 响应帧结构（与普通帧相似，帧号为 0xFF，数据段前 2 个字节为 ACK 标志，负载数据必须小于普通帧满数据大小，以确保被识别成孤立帧） + + unsigned char send_buffer[FRAME_SIZE]; + memset(send_buffer, 0, FRAME_SIZE); + + // 构造帧头 + unsigned short header = FRAME_HEADER; + memcpy(send_buffer, &header, 2); + // 构造帧序号和数据长度 + // memcpy(send_buffer + 2, 0xFF, 1); + *(send_buffer + 2) = 0xFF; + + length += 2; // 包含 ACK 标志长度 + if (length > DATA_SIZE) + { + return -1; // 数据超长 + } + + memcpy(send_buffer + 3, &length, 1); + + // magic number for ack + unsigned short ack_flag = 0x1926; + if (ack) + { + memcpy(send_buffer + HEADER_SIZE, &ack_flag, 2); + } + else + { + memset(send_buffer + HEADER_SIZE, 0, 2); + } + + // 拷贝该帧对应数据段 + memcpy(send_buffer + HEADER_SIZE + 2, data, length - 2); + + // 计算 CRC32 校验和 + unsigned long crc = calculate_crc32(send_buffer, HEADER_SIZE + DATA_SIZE + FEC_SIZE); + memcpy(send_buffer + HEADER_SIZE + DATA_SIZE + FEC_SIZE, &crc, CHECKSUM_SIZE); + + unsigned short tail = FRAME_TAIL; + memcpy(send_buffer + HEADER_SIZE + DATA_SIZE + FEC_SIZE + CHECKSUM_SIZE, &tail, TAIL_SIZE); + + // 发送响应帧 + if (by_serial_write(&serial_port, send_buffer, FRAME_SIZE) != 0) + { + return -2; // 发送失败 + } + + return 0; +} + // 初始化串口 static PyObject *serial_init(PyObject *self, PyObject *args) { @@ -202,7 +311,7 @@ static PyObject *serial_init(PyObject *self, PyObject *args) PyErr_SetString(PyExc_RuntimeError, "Failed to start receive thread"); return NULL; } - Py_RETURN_NONE; + Py_RETURN_TRUE; } // 发送数据 @@ -250,8 +359,27 @@ static PyObject *serial_send(PyObject *self, PyObject *args) frame_counter++; usleep(80000); } + + unsigned short ack_timeout = 10; + // 等待 ACK 响应 + while (!ack_flag) + { + usleep(100000); + if (ack_timeout-- == 0) + { + ack_flag = 0; + frame_counter = 0; + printf("ACK timeout\r\n"); + Py_RETURN_FALSE; + } + } + ack_flag = 0; frame_counter = 0; - Py_RETURN_NONE; + // Py_RETURN_TRUE; + // 返回 ACK 响应 + PyObject *result = Py_BuildValue("y#", recv_ack_data_buffer, ack_data_len); + ack_data_len = 0; + return result; } // 接收数据 @@ -274,18 +402,67 @@ static PyObject *serial_receive(PyObject *self, PyObject *args) return result; } +static PyObject *serial_set_ack_data(PyObject *self, PyObject *args) +{ + const char *input_data; // 用于存储输入的二进制数据 + Py_ssize_t input_length; // 用于存储输入数据的长度 + + // 解析参数，期望接收到一个 bytes 对象 + if (!PyArg_ParseTuple(args, "y#", &input_data, &input_length)) + { + PyErr_SetString(PyExc_TypeError, "Expected a bytes object"); + return NULL; + } + + // 检查输入数据是否为空 + if (input_length == 0) + { + PyErr_SetString(PyExc_ValueError, "Input data cannot be empty"); + return NULL; + } + + // 检查输入数据是否为空 + if (input_length > (DATA_SIZE - 2)) + { + PyErr_SetString(PyExc_ValueError, "Input data is too long"); + return NULL; + } + + // // 创建一个缓冲区用于存储处理后的数据 + // char *processed_data = (char *)malloc(input_length); + // if (processed_data == NULL) { + // PyErr_SetString(PyExc_MemoryError, "Failed to allocate memory"); + // return NULL; + // } + + // // 将处理后的数据封装为 Python 的 bytes 对象 + // PyObject *result = PyBytes_FromStringAndSize(processed_data, input_length); + + // // 释放分配的内存 + // free(processed_data); + + // // 返回结果 + // return result; + + memcpy(ack_data, input_data, input_length); + ack_data_len = input_length; + + Py_RETURN_NONE; +} + // 模块方法表 static PyMethodDef SerialMethods[] = { {"init", serial_init, METH_VARARGS, "Initialize serial port"}, {"send", serial_send, METH_VARARGS, "Send data over serial port"}, {"receive", serial_receive, METH_VARARGS, "Receive data from serial port"}, + {"set_ack_data", serial_set_ack_data, METH_VARARGS, "Set ACK data"}, {NULL, NULL, 0, NULL}}; // 模块定义 static struct PyModuleDef serialmodule = { PyModuleDef_HEAD_INIT, "serial_module", - NULL, + "A module to transfer serializable data over serial port", -1, SerialMethods};