Arduino IDE无法识别结构

Question

我正在尝试使用ESP-NOW将2个int变量从客户端发送到服务器。客户端的完整代码为：

/**
ESPNOW - Basic communication - Master
Date: 26th September 2017
Author: Arvind Ravulavaru <https://github.com/arvindr21>
Purpose: ESPNow Communication between a Master ESP32 and a Slave ESP32
Description: This sketch consists of the code for the Master module.
Resources: (A bit outdated)
a. https://espressif.com/sites/default/files/documentation/esp-now_user_guide_en.pdf
b. http://www.esploradores.com/practica-6-conexion-esp-now/
<< This Device Master >>
Flow: Master
Step 1 : ESPNow Init on Master and set it in STA mode
Step 2 : Start scanning for Slave ESP32 (we have added a prefix of `slave` to the SSID of slave for an easy setup)
Step 3 : Once found, add Slave as peer
Step 4 : Register for send callback
Step 5 : Start Transmitting data from Master to Slave
Flow: Slave
Step 1 : ESPNow Init on Slave
Step 2 : Update the SSID of Slave with a prefix of `slave`
Step 3 : Set Slave in AP mode
Step 4 : Register for receive callback and wait for data
Step 5 : Once data arrives, print it in the serial monitor
Note: Master and Slave have been defined to easily understand the setup.
Based on the ESPNOW API, there is no concept of Master and Slave.
Any devices can act as master or salve.
*/
#include <esp_now.h>
#include <WiFi.h>
// Global copy of slave
esp_now_peer_info_t slave;
#define CHANNEL 1
#define PRINTSCANRESULTS 0
#define DELETEBEFOREPAIR 0
// Init ESP Now with fallback
void InitESPNow() {
WiFi.disconnect();
if (esp_now_init() == ESP_OK) {
Serial.println("ESPNow Init Success");
}
else {
Serial.println("ESPNow Init Failed");
// Retry InitESPNow, add a counte and then restart?
// InitESPNow();
// or Simply Restart
ESP.restart();
}
}
// Scan for slaves in AP mode
void ScanForSlave() {
int8_t scanResults = WiFi.scanNetworks();
// reset on each scan
bool slaveFound = 0;
memset(&slave, 0, sizeof(slave));
Serial.println("");
if (scanResults == 0) {
Serial.println("No WiFi devices in AP Mode found");
} else {
Serial.print("Found "); Serial.print(scanResults); Serial.println(" devices ");
for (int i = 0; i < scanResults; ++i) {
// Print SSID and RSSI for each device found
String SSID = WiFi.SSID(i);
int32_t RSSI = WiFi.RSSI(i);
String BSSIDstr = WiFi.BSSIDstr(i);
if (PRINTSCANRESULTS) {
Serial.print(i + 1);
Serial.print(": ");
Serial.print(SSID);
Serial.print(" (");
Serial.print(RSSI);
Serial.print(")");
Serial.println("");
}
delay(10);
// Check if the current device starts with `Slave`
if (SSID.indexOf("Slave") == 0) {
// SSID of interest
Serial.println("Found a Slave.");
Serial.print(i + 1); Serial.print(": "); Serial.print(SSID); Serial.print(" ["); Serial.print(BSSIDstr); Serial.print("]"); Serial.print(" ("); Serial.print(RSSI); Serial.print(")"); Serial.println("");
// Get BSSID => Mac Address of the Slave
int mac[6];
if ( 6 == sscanf(BSSIDstr.c_str(), "%x:%x:%x:%x:%x:%x",  &mac[0], &mac[1], &mac[2], &mac[3], &mac[4], &mac[5] ) ) {
for (int ii = 0; ii < 6; ++ii ) {
slave.peer_addr[ii] = (uint8_t) mac[ii];
}
}
slave.channel = CHANNEL; // pick a channel
slave.encrypt = 0; // no encryption
slaveFound = 1;
// we are planning to have only one slave in this example;
// Hence, break after we find one, to be a bit efficient
break;
}
}
}
if (slaveFound) {
Serial.println("Slave Found, processing..");
} else {
Serial.println("Slave Not Found, trying again.");
}
// clean up ram
WiFi.scanDelete();
}
// Check if the slave is already paired with the master.
// If not, pair the slave with master
bool manageSlave() {
if (slave.channel == CHANNEL) {
if (DELETEBEFOREPAIR) {
deletePeer();
}
Serial.print("Slave Status: ");
// check if the peer exists
bool exists = esp_now_is_peer_exist(slave.peer_addr);
if ( exists) {
// Slave already paired.
Serial.println("Already Paired");
return true;
} else {
// Slave not paired, attempt pair
esp_err_t addStatus = esp_now_add_peer(&slave);
if (addStatus == ESP_OK) {
// Pair success
Serial.println("Pair success");
return true;
} else if (addStatus == ESP_ERR_ESPNOW_NOT_INIT) {
// How did we get so far!!
Serial.println("ESPNOW Not Init");
return false;
} else if (addStatus == ESP_ERR_ESPNOW_ARG) {
Serial.println("Invalid Argument");
return false;
} else if (addStatus == ESP_ERR_ESPNOW_FULL) {
Serial.println("Peer list full");
return false;
} else if (addStatus == ESP_ERR_ESPNOW_NO_MEM) {
Serial.println("Out of memory");
return false;
} else if (addStatus == ESP_ERR_ESPNOW_EXIST) {
Serial.println("Peer Exists");
return true;
} else {
Serial.println("Not sure what happened");
return false;
}
}
} else {
// No slave found to process
Serial.println("No Slave found to process");
return false;
}
}
void deletePeer() {
esp_err_t delStatus = esp_now_del_peer(slave.peer_addr);
Serial.print("Slave Delete Status: ");
if (delStatus == ESP_OK) {
// Delete success
Serial.println("Success");
} else if (delStatus == ESP_ERR_ESPNOW_NOT_INIT) {
// How did we get so far!!
Serial.println("ESPNOW Not Init");
} else if (delStatus == ESP_ERR_ESPNOW_ARG) {
Serial.println("Invalid Argument");
} else if (delStatus == ESP_ERR_ESPNOW_NOT_FOUND) {
Serial.println("Peer not found.");
} else {
Serial.println("Not sure what happened");
}
}
//=================DATA======================
typedef struct test_struct {
int x;
int y;
} test_struct;
test_struct test;
test.x = 10;
test.y = 20;
//uint8_t data = 0;
// send data
void sendData() {
//data++;
const uint8_t *peer_addr = slave.peer_addr;
Serial.print("Sending: "); Serial.println(test);
esp_err_t result = esp_now_send(peer_addr, (uint8_t *) &test,
sizeof(test_struct));
Serial.print("Send Status: ");
if (result == ESP_OK) {
Serial.println("Success");
} else if (result == ESP_ERR_ESPNOW_NOT_INIT) {
// How did we get so far!!
Serial.println("ESPNOW not Init.");
} else if (result == ESP_ERR_ESPNOW_ARG) {
Serial.println("Invalid Argument");
} else if (result == ESP_ERR_ESPNOW_INTERNAL) {
Serial.println("Internal Error");
} else if (result == ESP_ERR_ESPNOW_NO_MEM) {
Serial.println("ESP_ERR_ESPNOW_NO_MEM");
} else if (result == ESP_ERR_ESPNOW_NOT_FOUND) {
Serial.println("Peer not found.");
} else {
Serial.println("Not sure what happened");
}
}
// callback when data is sent from Master to Slave
void OnDataSent(const uint8_t *mac_addr, esp_now_send_status_t status) {
char macStr[18];
snprintf(macStr, sizeof(macStr), "%02x:%02x:%02x:%02x:%02x:%02x",
mac_addr[0], mac_addr[1], mac_addr[2], mac_addr[3], mac_addr[4], mac_addr[5]);
Serial.print("Last Packet Sent to: "); Serial.println(macStr);
Serial.print("Last Packet Send Status: "); Serial.println(status == ESP_NOW_SEND_SUCCESS ? "Delivery Success" : "Delivery Fail");
}
void setup() {
Serial.begin(115200);
//Set device in STA mode to begin with
WiFi.mode(WIFI_STA);
Serial.println("ESPNow/Basic/Master Example");
// This is the mac address of the Master in Station Mode
Serial.print("STA MAC: "); Serial.println(WiFi.macAddress());
// Init ESPNow with a fallback logic
InitESPNow();
// Once ESPNow is successfully Init, we will register for Send CB to
// get the status of Trasnmitted packet
esp_now_register_send_cb(OnDataSent);
}
void loop() {
// In the loop we scan for slave
ScanForSlave();
// If Slave is found, it would be populate in `slave` variable
// We will check if `slave` is defined and then we proceed further
if (slave.channel == CHANNEL) { // check if slave channel is defined
// `slave` is defined
// Add slave as peer if it has not been added already
bool isPaired = manageSlave();
if (isPaired) {
// pair success or already paired
// Send data to device
sendData();
} else {
// slave pair failed
Serial.println("Slave pair failed!");
}
}
else {
// No slave found to process
}
// wait for 3seconds to run the logic again
delay(3000);
}

当发送的数据只有0时，当我替换这个结构(它刚刚超过主代码中的===========data==========行(时，一切都正常了

typedef struct test_struct {
int x;
int y;
} test_struct;
test_struct test;
test.x = 10;
test.y = 20;

我收到一条错误消息"test"未命名类型。

有什么想法吗？

Answer 1

我想明白了，结构定义必须在函数内部，无论是设置还是其他。谢谢大家看这个

好吧，我以为我已经想通了，但我只是写了另一个草图，把结构放在所有函数之前，它正在工作，所以说实话，我不知道发生了什么，其他人都知道答案，或者这个问题太愚蠢了，没人想评论吗？这对我来说很好，我在这方面仍然是一个很好的新手，所以如果你能帮忙，很好，如果不能，无论如何，谢谢你，这对新手来说仍然是一种很好的资源😅

Answer 2

您试图在任何可执行代码之外分配一个值进行测试。定义很好，赋值测试.x=10是需要在新的或现有的函数(如setup((或loop(((中执行的代码。请尝试在初始化期间分配值，如下所示。这样，编译器在为该变量分配内存时就会将值放入。

typedef struct{
int x;
int y;
} test_struct;
test_struct t={10,20};