210 lines
7.7 KiB
Plaintext
210 lines
7.7 KiB
Plaintext
|
# Modbus RTU 报文说明
|
|||
|
|
|
|||
|
|
本文档描述 STM32 通过 RS485 接口轮询 Noris AMS 模块的 Modbus RTU 通信协议，
|
|||
|
|
以及报警数据如何通过 RF433 无线上报。
|
|||
|
|
|
|||
|
|
---
|
|||
|
|
|
|||
|
|
## 1. Modbus RTU 请求帧 (MCU → Noris AMS)
|
|||
|
|
|
|||
|
|
```text
|
|||
|
|
01 03 04 88 00 01 C5 D3
|
|||
|
|
-- -- -- -- -- -- -- --
|
|||
|
|
| | | | | | | |
|
|||
|
|
| | | | | | | +-- CRC16 低字节
|
|||
|
|
| | | | | | +------ CRC16 高字节
|
|||
|
|
| | | | | +---------- 读取数量 = 1 个寄存器 (00 01)
|
|||
|
|
| | | +------------------ 寄存器起始地址 = 0x0488 = 1160 (Noris 41161)
|
|||
|
|
| | +---------------------- 功能码 = 0x03 (Read Holding Registers)
|
|||
|
|
| +-------------------------- 从站地址 = 1
|
|||
|
|
+------------------------------ 固定从站地址
|
|||
|
|
```
|
|||
|
|
|
|||
|
|
- 帧长度: 8 字节
|
|||
|
|
- 发送间隔: 1000ms (MODBUS_RTU_POLL_INTERVAL)
|
|||
|
|
- 发送方式: HAL_UART_Transmit() 阻塞发送, @19200bps 约 4.2ms
|
|||
|
|
|
|||
|
|
---
|
|||
|
|
|
|||
|
|
## 2. Modbus RTU 正常响应帧 (Noris AMS → MCU)
|
|||
|
|
|
|||
|
|
```text
|
|||
|
|
01 03 02 00 F0 B8 47
|
|||
|
|
-- -- -- -- -- -- --
|
|||
|
|
| | | | | | |
|
|||
|
|
| | | | | | +-- CRC16 高字节
|
|||
|
|
| | | | | +------ CRC16 低字节
|
|||
|
|
| | | | +---------- 寄存器值低字节 = 0xF0
|
|||
|
|
| | | +-------------- 寄存器值高字节 = 0x00 (大端序)
|
|||
|
|
| | +------------------ 数据字节数 = 2 (1个寄存器 × 2字节)
|
|||
|
|
| +---------------------- 功能码 = 0x03 (正常响应)
|
|||
|
|
+-------------------------- 从站地址 = 1
|
|||
|
|
```
|
|||
|
|
|
|||
|
|
- 帧长度: 7 字节
|
|||
|
|
- 寄存器值: 0x00F0 (大端序)
|
|||
|
|
|
|||
|
|
---
|
|||
|
|
|
|||
|
|
## 3. 寄存器值 → 报警位映射
|
|||
|
|
|
|||
|
|
寄存器 41161 值为 0x00F0 时的位分布:
|
|||
|
|
|
|||
|
|
```text
|
|||
|
|
Bit: 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
|
|||
|
|
0 0 0 0 0 0 0 0 1 1 1 1 0 0 0 0
|
|||
|
|
↑ ↑ ↑ ↑
|
|||
|
|
│ │ │ └─ Bit4: 火灾综合报警 (Fire)
|
|||
|
|
│ │ └──── Bit5: 水密门综合报警 (Door)
|
|||
|
|
│ └─────── Bit6: 舱底水综合报警 (Bilge)
|
|||
|
|
└────────── Bit7: 气体检测综合报警 (Gas)
|
|||
|
|
```
|
|||
|
|
|
|||
|
|
提取宏定义 (modbus_rtu_master.h):
|
|||
|
|
```c
|
|||
|
|
NORIS_FIRE_ALARM(reg) = (reg >> 4) & 1 // Bit4 → 报警字节 Bit0
|
|||
|
|
NORIS_DOOR_ALARM(reg) = (reg >> 5) & 1 // Bit5 → 报警字节 Bit1
|
|||
|
|
NORIS_BILGE_ALARM(reg) = (reg >> 6) & 1 // Bit6 → 报警字节 Bit2
|
|||
|
|
NORIS_GAS_ALARM(reg) = (reg >> 7) & 1 // Bit7 → 报警字节 Bit3
|
|||
|
|
```
|
|||
|
|
|
|||
|
|
映射后的紧凑报警字节 (0x00F0 → 0x0F):
|
|||
|
|
|
|||
|
|
```text
|
|||
|
|
Bit: 7 6 5 4 3 2 1 0
|
|||
|
|
0 0 0 0 1 1 1 1
|
|||
|
|
↑ ↑ ↑ ↑
|
|||
|
|
│ │ │ └─ Bit0: 火灾报警
|
|||
|
|
│ │ └──── Bit1: 水密门报警
|
|||
|
|
│ └─────── Bit2: 舱底水报警
|
|||
|
|
└────────── Bit3: 气体检测报警
|
|||
|
|
```
|
|||
|
|
|
|||
|
|
---
|
|||
|
|
|
|||
|
|
## 4. 报警状态变化上报 (主动上报, Type 0x10)
|
|||
|
|
|
|||
|
|
当 Modbus RTU 报警状态发生变化时，立即发送此包。
|
|||
|
|
格式与原 DI 变化通知完全一致，上位机代码无需修改。
|
|||
|
|
|
|||
|
|
```text
|
|||
|
|
AA 10 03 ID XX SUM
|
|||
|
|
-- -- -- -- -- ---
|
|||
|
|
| | | | | |
|
|||
|
|
| | | | | +-- 校验和
|
|||
|
|
| | | | +------ 报警状态字节 (见第3节报警字节定义)
|
|||
|
|
| | | +---------- 本机设备 ID
|
|||
|
|
| | +-------------- 长度固定为 0x03 (ID + 1字节状态 + SUM)
|
|||
|
|
| +------------------ 类型标识：0x10 (I/O Data)
|
|||
|
|
+---------------------- 固定起始符
|
|||
|
|
```
|
|||
|
|
|
|||
|
|
示例 (设备ID=105, 报警=0x0F):
|
|||
|
|
```text
|
|||
|
|
AA 10 03 69 0F [SUM]
|
|||
|
|
```
|
|||
|
|
|
|||
|
|
触发条件: Modbus RTU 轮询到报警状态变化，且非首次轮询结果。
|
|||
|
|
|
|||
|
|
---
|
|||
|
|
|
|||
|
|
## 5. 系统心跳包 (30秒/次, Type 0xAA)
|
|||
|
|
|
|||
|
|
```text
|
|||
|
|
AA AA 09 ID [SEQ_H] [SEQ_L] [FW_H] [FW_L] [RTU] [TCP_H] [TCP_L] SUM
|
|||
|
|
-- -- -- -- --------------- ------------- ---- --------------- ---
|
|||
|
|
| | | | | | | | |
|
|||
|
|
| | | | | | | | +-- 校验和
|
|||
|
|
| | | | | | | +------------- Modbus TCP 寄存器值
|
|||
|
|
| | | | | | +------------------------ Modbus RTU 报警状态
|
|||
|
|
| | | | | | Bit0:火灾 Bit1:水密门
|
|||
|
|
| | | | | | Bit2:舱底水 Bit3:气体检测
|
|||
|
|
| | | | | +------------------------------------ 固件版本编码
|
|||
|
|
| | | | +--------------------------------------------------- 序列号 (0-65535)
|
|||
|
|
| | | +------------------------------------------------------------- 本机设备 ID
|
|||
|
|
| | +----------------------------------------------------------------- LEN = 9
|
|||
|
|
| +--------------------------------------------------------------------- 类型 0xAA
|
|||
|
|
+------------------------------------------------------------------------- 固定起始符
|
|||
|
|
```
|
|||
|
|
|
|||
|
|
Payload 字段说明:
|
|||
|
|
|
|||
|
|
| 偏移 | 字段 | 长度 | 说明 |
|
|||
|
|
|------|----------|------|------|
|
|||
|
|
| 0-1 | SEQ | 2 | 序列号 (16-bit 大端, 0-65535 循环自增) |
|
|||
|
|
| 2-3 | FW | 2 | 固件版本编码 (MAKE_XTELL_CODE 宏) |
|
|||
|
|
| 4 | RTU | 1 | Modbus RTU 报警状态字节 (原 DI 状态位，现替换为报警位) |
|
|||
|
|
| 5-6 | TCP | 2 | Modbus TCP 最后寄存器值 (0xFFFF 表示无效) |
|
|||
|
|
|
|||
|
|
---
|
|||
|
|
|
|||
|
|
## 6. Modbus RTU 异常响应帧 (参考)
|
|||
|
|
|
|||
|
|
如果从站返回异常:
|
|||
|
|
|
|||
|
|
```text
|
|||
|
|
01 83 02 C0 F1
|
|||
|
|
-- -- -- -- --
|
|||
|
|
| | | | |
|
|||
|
|
| | | | +-- CRC16 校验
|
|||
|
|
| | | +------ 异常码 = 02 (非法寄存器地址)
|
|||
|
|
| | +---------- 功能码 + 0x80 (异常标志, 0x03 → 0x83)
|
|||
|
|
| +-------------- 从站地址
|
|||
|
|
+------------------
|
|||
|
|
```
|
|||
|
|
|
|||
|
|
处理: 异常响应 FC ≠ 0x03，被 parse_modbus_response() 中
|
|||
|
|
mb_rx_buf[1] != 0x03 判断拦截，静默丢弃。
|
|||
|
|
|
|||
|
|
---
|
|||
|
|
|
|||
|
|
## 7. 状态机与轮询时序
|
|||
|
|
|
|||
|
|
### 7.1 状态机
|
|||
|
|
|
|||
|
|
```text
|
|||
|
|
IDLE ──[1000ms到]──> WAIT_POLL ──[立即发送]──> WAIT_RESPONSE
|
|||
|
|
↑ │
|
|||
|
|
│ ┌─────────────┤
|
|||
|
|
│ │ │
|
|||
|
|
│ [帧接收完成] [超时500ms]
|
|||
|
|
│ │ │
|
|||
|
|
└──────────── PROCESS ←─────────┘ │
|
|||
|
|
│ │
|
|||
|
|
│ (解析+更新报警) │
|
|||
|
|
└────────────────────────────────┘
|
|||
|
|
```
|
|||
|
|
|
|||
|
|
### 7.2 轮询时序示例
|
|||
|
|
|
|||
|
|
```text
|
|||
|
|
时间 0ms 1000ms 2000ms 3000ms
|
|||
|
|
│ │ │ │
|
|||
|
|
T0 ├─TX(8B,4ms)
|
|||
|
|
├─RX(7B,4ms)
|
|||
|
|
├─解析
|
|||
|
|
│
|
|||
|
|
T1 ├─TX
|
|||
|
|
├─RX
|
|||
|
|
├─解析
|
|||
|
|
│
|
|||
|
|
T2 ├─TX
|
|||
|
|
├─超时500ms
|
|||
|
|
├─回IDLE
|
|||
|
|
│
|
|||
|
|
T3 ├─TX
|
|||
|
|
├─RX
|
|||
|
|
├─解析
|
|||
|
|
```
|
|||
|
|
|
|||
|
|
每秒一个完整轮询周期: 发送(~4ms) + 等响应(~10ms) + 解析(<1ms) ≈ 15ms，其余 985ms 空闲。
|
|||
|
|
|
|||
|
|
### 7.3 关键超时参数
|
|||
|
|
|
|||
|
|
| 参数 | 值 | 说明 |
|
|||
|
|
|------|------|------|
|
|||
|
|
| MODBUS_RTU_POLL_INTERVAL | 1000ms | 轮询间隔 |
|
|||
|
|
| MODBUS_RTU_RESP_TIMEOUT | 500ms | 响应超时 |
|
|||
|
|
| MODBUS_RTU_INTER_CHAR_TIMEOUT | 10ms | 帧内字符间隔超时 |
|
|||
|
|
| MODBUS_RTU_TX_ECHO_MARGIN | 10ms | 发送回波屏蔽时间 |
|