/// <summary>读取寄存器 输入寄存器/保持寄存器</summary>
/// <remarks>
/// 保持寄存器
/// 请求：0x03|2字节起始地址|2字节寄存器数量（1~2000）
/// 响应：0x03|1字节字节数|n*2字节寄存器值
///
/// 输入寄存器
/// 请求：0x04|2字节起始地址|2字节输入寄存器数量（1~2000）
/// 响应：0x04|1字节字节数|n*2字节输入寄存器
/// </remarks>
/// <param name="entity"></param>
/// <returns></returns>
ModbusEntity ReadRegisters(ModbusEntity entity)
{
var data = entity.Data;
// 无效功能指令
if (data == null || data.Length != 4)
{
return(entity.SetError(Errors.MessageLength));
}
var addr = data.ReadUInt16(0);
var count = data.ReadUInt16(2);
// 输出数量不正确 count <= 0x07D0=2000
//if (count == 0 || count > 0x07D0) return entity.SetError(3);
if (count == 0)
{
return(entity.SetError(Errors.Count));
}
IWordStore store = null;
#if DEBUG
var func = "";
#endif
switch (entity.Function)
{
case MBFunction.ReadHoldingRegisters:
store = DataStore.HoldingRegisters;
#if DEBUG
func = "ReadHoldingRegisters";
#endif
break;
case MBFunction.ReadInputRegisters:
store = DataStore.InputRegisters;
#if DEBUG
func = "ReadInputRegisters";
#endif
break;
default:
break;
}
if (count > store.Count)
{
return(entity.SetError(Errors.Count));
}
// 起始地址+数量 不正确
if (addr + count > 0xFFFF)
{
return(entity.SetError(Errors.Address));
}
#if DEBUG
WriteLine(func + "(0x" + addr.ToString("X2") + ", 0x" + count.ToString("X2") + ")");
#endif
if (OnReadRegister != null)
{
OnReadRegister(entity, addr, count);
}
var buf = new Byte[1 + count * 2];
buf[0] = (Byte)(count * 2);
for (var i = 0; i < count; i++)
{
buf.WriteUInt16(1 + i * 2, store.Read(addr + i));
}
// 读出来
entity.Data = buf;
return(entity);
}
/// <summary>读取整个UInt32</summary>
/// <param name="store"></param>
/// <param name="i"></param>
/// <returns></returns>
public static UInt32 ReadUInt32(this IWordStore store, Int32 i)
{
return((UInt32)((store.Read(i) << 16) + store.Read(i + 1)));
}