--- title: "Dancing with Wolves – Installing an M416 Fully Automatic Water Gun on a Go2 (Part 2)" url: "https://maker.wiznet.io/gavinchang/projects/dancing-with-wolves--installing-an-m416-fully-automatic-water-gun-on-a-go2-part-2/" markdown_url: "https://maker.wiznet.io/gavinchang/projects/dancing-with-wolves--installing-an-m416-fully-automatic-water-gun-on-a-go2-part-2/md" type: "UCC: User Created Content" author: "Snotty Fish" author_url: "https://www.cnblogs.com/shenwx/p/19126089" editor: "WIZnet" editor_url: "https://maker.wiznet.io/" original_author: "Snotty Fish" original_url: "https://www.cnblogs.com/shenwx/p/19126089" published: "2025-12-04" language: "en" likes: 0 views: 500 comments: 0 source: "WIZnet Makers (https://maker.wiznet.io/)" --- # Dancing with Wolves – Installing an M416 Fully Automatic Water Gun on a Go2 (Part 2) > Dancing with Wolves – Installing an M416 Fully Automatic Water Gun on a Go2 (Part 2) Original author: Snotty Fish (source: https://www.cnblogs.com/shenwx/p/19126089) ## Article ## **Introduction** As this is the opening chapter of the series, it's necessary to make some agreements first: - The following content will only provide the code for the core functions, keeping it as concise as possible. After all, every dog ​​owner will have their own ideas and will add their own functions. Writing too much code will make it difficult to integrate, not to mention that I haven't made any complex functions. - The provided code snippets will not be explained in detail; programming languages ​​are languages, so just "grasp the spirit" is enough. - Whether it's hardware design or software programming, we follow the design philosophy of the Indian military industry: we will never code our own code if we can rely on existing software functions, and we will never make our own electronic modules if we can buy them. - The robot operating system employs `Ros2 Foxy`software programming `python`languages ​​and hardware programming `c`languages `Ubuntu 20.04`. ## **Function** The functions described here refer only to those related to mounting the gun. (The water gun was a gift from my son; please do not shoot it at people.) - The bracket and electrical box are printed using a 3D printer to hold the gun and circuit board. - The go2 dock sends a UDP broadcast message to the control circuit, which then fires. - Programmatically implement the original remote control `向上按钮`as the fire button. - Implement `cv2`a simple face recognition system. - Implement a `deepseek agent`feature that allows Go2 to understand your commands and execute tasks accordingly (e.g., find Zhang San and fire immediately, or say hello...). ![](https://maker.wiznet.io/upload/ckeditor5/1066384665%5F1764848496%2Epng) ## **hardware** First, here's a picture, the actual wiring diagram: ![](https://maker.wiznet.io/upload/ckeditor5/1066384665%5F1764848515%2Epng) The boards in the picture were all purchased from Taobao. The control board cost around 150 yuan, the DC-DC module cost around 2 yuan, and the electronic switch cost less than 1 yuan. ### **1. Water bullet gun** The M416 automatic rifle I use in PUBG was bought many years ago; I don't remember how much it cost. It also had many accessories, but I've lost them all. It's a bit worn out, but it still works, and it's very relaxing to play with. It's powered by two 18650 batteries (3.7V + 3.7V = 7.4V), but the batteries have deteriorated over time. Therefore, I draw power from the 12V output of my Go2 and supply it to the rifle through an adjustable DC-DC step-down module. ### **2. Control board** I bought a development board before, which had an STM32F103C8T6 chip, a W5500 Ethernet module, two CAN channels, and two 485 channels, for about 150 yuan. Actually, you don't need so many functions to control the gun. All you need is a board with a W5500 Ethernet module and GPIO output. The GPIO ports control the electronic switches to power the gun. ### **3. DC-DC module** Reduce the DC voltage of go2 from 12V to 7.4V. ### **4. Electronic switch** It receives GPIO control signals to turn the gun's power on or off; the gun fires when it has power. (The trigger of the gun is strapped to the firing position.) ## **Control Program** - **STM32CubeMX** ![](https://maker.wiznet.io/upload/ckeditor5/1066384665%5F1764848535%2Epng) **Porting the W5500 driver library** -- 1. Download the W5500 driver library [from Gitee](https://gitee.com/Inspirelsd/w5500_ioLibrary_Driver) or [GitHub](https://github.com/Wiznet/ioLibrary_Driver) . `ioLibrary_Driver`Copy the directory to your project. -- 2. Add `ioLibrary_Driver\Ethernet`the three files in the directory and their header files -- `w5500.c`, `wizchip_conf.c`, `socket.c`to your project. **Control Program** This part of the code uses `FreeRTOS`the operating system and listens `UDP 5001`on a port. When a message containing a string is received `fire`, port PB7 remains high for one second. In other words, when a UDP message is received `fire`, the M416 fires for one second. ```plaintext /* USER CODE END Header_StartTaskSendMsg */ void StartTaskGetMsg(void *argument) { /* USER CODE BEGIN StartTaskSendMsg */ /* Infinite loop */ for(;;) { do_udp(); if (fired == 1) { HAL_GPIO_WritePin(GPIOB,GPIO_PIN_7,GPIO_PIN_SET); osDelay(1000); HAL_GPIO_TogglePin(GPIOB,GPIO_PIN_7); fired = 0; } osDelay(1000); } /* USER CODE END StartTaskSendMsg */ } ``` `myudp.c`The program defines the W5500's network information, including the listening port and IP address, and processes received messages. (myudp.h ) ```cpp #ifndef MYUDP_H #define MYUDP_H #include "myudp.h" #include "main.h" #include "w5500.h" #include "socket.h" #include "wizchip_conf.h" #include "spi.h" #include #define SOCK_UDPS 2 extern uint8_t buff[128]; extern uint8_t UDP_send_buff[128]; extern uint8_t remote_ip[4]; extern uint16_t remote_port; void UDPinit(void); void do_udp(void); void udp_send(uint8_t* data, uint8_t len); void Analysis(uint8_t *buf); #endif // MYUDP_H ``` Here you can modify your IP address, listen on the port, and process received messages. (myudp.c) ```cpp #include "myudp.h" #include "main.h" #include "w5500.h" #include "socket.h" #include "wizchip_conf.h" #include "spi.h" #include uint8_t buff[128]; uint8_t UDP_send_buff[128]; uint8_t remote_ip[4] = {255,255,255,255}; uint16_t remote_port = 8080; //片选 void W5500_Select(void) { HAL_GPIO_WritePin(SCSn_GPIO_Port, SCSn_Pin, GPIO_PIN_RESET); } void W5500_Unselect(void) { HAL_GPIO_WritePin(SCSn_GPIO_Port, SCSn_Pin, GPIO_PIN_SET); } void W5500_Restart(void) { HAL_GPIO_WritePin(RSTn_GPIO_Port, RSTn_Pin, GPIO_PIN_RESET); HAL_Delay(1); // delay 1ms HAL_GPIO_WritePin(RSTn_GPIO_Port, RSTn_Pin, GPIO_PIN_SET); HAL_Delay(1600); // delay 1600ms } void W5500_ReadBuff(uint8_t* buff, uint16_t len) { HAL_SPI_Receive(&hspi2, buff, len, HAL_MAX_DELAY); } void W5500_WriteBuff(uint8_t* buff, uint16_t len) { HAL_SPI_Transmit(&hspi2, buff, len, HAL_MAX_DELAY); } uint8_t W5500_ReadByte(void) { uint8_t byte; W5500_ReadBuff(&byte, sizeof(byte)); return byte; } void W5500_WriteByte(uint8_t byte) { W5500_WriteBuff(&byte, sizeof(byte)); } //配置W5500网络信息 wiz_NetInfo gSetNetInfo = { .mac = {0x00, 0x08, 0xdc, 0x11, 0x11, 0x11}, .ip = {192, 168, 123, 55}, .sn = {255, 255, 255, 0}, .gw = {192, 168, 123, 1}, .dns = {144, 144, 144, 144}, .dhcp = NETINFO_STATIC}; wiz_NetInfo gGetNetInfo; enum Status { Failed = 0, Success = 1 }; /** * @brief valid the result of set net info * @return 1: Success * 0: Failed */ uint8_t validSetNetInfoResult(wiz_NetInfo* _set, wiz_NetInfo* _get) { return (!memcmp(_set, _get, sizeof(wiz_NetInfo))); // if same, memcmp return 0 } void UDPinit(void) { reg_wizchip_cs_cbfunc(W5500_Select, W5500_Unselect); reg_wizchip_spi_cbfunc(W5500_ReadByte, W5500_WriteByte); W5500_Restart(); // hardware restart through RESET pin ctlnetwork(CN_SET_NETINFO, (void*)&gSetNetInfo); // set net info // maybe need delay ctlnetwork(CN_GET_NETINFO, (void*)&gGetNetInfo); // get net info // W5500 has 8 channel, 32k buffer, 2 means 2KBytes uint8_t buffer_size_8channel_tx_rx[16] = {2, 2, 2, 2, 2, 2, 2, 2, // 8 channel tx 2, 2, 2, 2, 2, 2, 2, 2}; // 8 channel rx if(ctlwizchip(CW_INIT_WIZCHIP,(void*)buffer_size_8channel_tx_rx)) { // failed } uint8_t sta = getSn_SR(SOCK_UDPS); if(sta == SOCK_CLOSED) { socket(SOCK_UDPS, Sn_MR_UDP, 5001, 0); } HAL_Delay(100); } void do_udp(void) { uint16_t len=0; switch(getSn_SR(SOCK_UDPS)) /*获取socket的状态*/ { case SOCK_CLOSED: /*socket处于关闭状态*/ socket(SOCK_UDPS,Sn_MR_UDP,5001,0); /*初始化socket*/ break; case SOCK_UDP: /*socket初始化完成*/ HAL_Delay(10); if(getSn_IR(SOCK_UDPS) & Sn_IR_RECV) //检查是否有接收中断 { setSn_IR(SOCK_UDPS, Sn_IR_RECV); /*清接收中断*/ } if((len=getSn_RX_RSR(SOCK_UDPS))>0) /*接收到数据*/ { recvfrom(SOCK_UDPS,buff, len, remote_ip,&remote_port); /*W5500接收计算机发送来的数据W5500接收计算机发送来的数据，并获取发送方的IP地址和端口号*/ sendto(SOCK_UDPS,buff,len-8, remote_ip, remote_port); /*W5500把接收到的数据发送*/ Analysis(buff);//分析数据 memset(buff, 0, sizeof(buff)); } break; } } void udp_send(uint8_t* data,uint8_t len) { sendto(SOCK_UDPS, data, len, remote_ip, remote_port); memset(data, 0, len); } void SystemReset() { __HAL_RCC_BACKUPRESET_FORCE(); // 强制备份域复位 __HAL_RCC_BACKUPRESET_RELEASE(); // 释放备份域复位 NVIC_SystemReset(); // 发起系统复位 } void Analysis(uint8_t *buf) { char * gun = "fire"; char * result = strstr((char*)buf, gun); if (result != NULL) { fired =1; return; } char * devreset ="reset"; result = strstr((char*)buf, devreset); if (result != NULL) { SystemReset(); return; } } ``` --- Source: https://maker.wiznet.io/gavinchang/projects/dancing-with-wolves--installing-an-m416-fully-automatic-water-gun-on-a-go2-part-2/