6 Commits

3 changed files with 100 additions and 66 deletions

View File

@@ -1188,15 +1188,9 @@ func (mc *ModbusClient) readRegistersWithFunctionCode(addr uint16, quantity uint
unitId: mc.unitId,
}
// if functionCode != fcCustomize {
// err = ErrUnexpectedParameters
// mc.logger.Errorf("unexpected function code (%d)", functionCode)
// return
// }
if functionCode == 0 {
if functionCode != fcCustomize {
err = ErrUnexpectedParameters
mc.logger.Errorf("unexpected register type (%v)", functionCode)
mc.logger.Errorf("unexpected function code (%d)", functionCode)
return
}
@@ -1208,7 +1202,8 @@ func (mc *ModbusClient) readRegistersWithFunctionCode(addr uint16, quantity uint
return
}
if quantity > 1024 {
// 16 * 16 * 40
if quantity > 10240 {
err = ErrUnexpectedParameters
mc.logger.Error("quantity of registers exceeds 1024")
return
@@ -1232,21 +1227,53 @@ func (mc *ModbusClient) readRegistersWithFunctionCode(addr uint16, quantity uint
}
// validate the response code
// switch {
// case res.functionCode == req.functionCode:
// // make sure the payload length is what we expect
// // (1 byte of length + 2 bytes per register)
// if len(res.payload) != 1+2*int(quantity) {
// err = ErrProtocolError
// return
// }
// // validate the byte count field
// // (2 bytes per register * number of registers)
// if uint(res.payload[0]) != 2*uint(quantity) {
// err = ErrProtocolError
// return
// }
// // remove the byte count field from the returned slice
// bytes = res.payload[1:]
// case res.functionCode == (req.functionCode | 0x80):
// if len(res.payload) != 1 {
// err = ErrProtocolError
// return
// }
// err = mapExceptionCodeToError(res.payload[0])
// default:
// err = ErrProtocolError
// mc.logger.Warningf("unexpected response code (%v)", res.functionCode)
// }
switch {
case res.functionCode == req.functionCode:
// make sure the payload length is what we expect
// (1 byte of length + 2 bytes per register)
if len(res.payload) != 1+2*int(quantity) {
err = ErrProtocolError
return
}
// if len(res.payload) != 1+2*int(quantity) {
// err = ErrProtocolError
// return
// }
// validate the byte count field
// (2 bytes per register * number of registers)
if uint(res.payload[0]) != 2*uint(quantity) {
err = ErrProtocolError
return
}
// if uint(res.payload[0]) != 2*uint(quantity) {
// err = ErrProtocolError
// return
// }
// remove the byte count field from the returned slice
bytes = res.payload[1:]

View File

@@ -41,7 +41,7 @@ const (
fcWriteFileRecord uint8 = 0x15
// customize
fcCustomize uint8 = 0x29
fcCustomize uint8 = 0x41
// exception codes
exIllegalFunction uint8 = 0x01

View File

@@ -21,10 +21,10 @@ type rtuTransport struct {
}
type rtuLink interface {
Close() (error)
Close() error
Read([]byte) (int, error)
Write([]byte) (int, error)
SetDeadline(time.Time) (error)
SetDeadline(time.Time) error
}
// Returns a new RTU transport.
@@ -140,7 +140,7 @@ func (rt *rtuTransport) readRTUFrame() (res *pdu, err error) {
var bytesNeeded int
var crc crc
rxbuf = make([]byte, maxRTUFrameLength)
rxbuf = make([]byte, 10243)
// read the serial ADU header: unit id (1 byte), function code (1 byte) and
// PDU length/exception code (1 byte)
@@ -222,12 +222,16 @@ func expectedResponseLenth(responseCode uint8, responseLength uint8) (byteCount
case fcReadHoldingRegisters,
fcReadInputRegisters,
fcReadCoils,
fcReadDiscreteInputs: byteCount = int(responseLength)
fcReadDiscreteInputs,
0x41:
byteCount = int(responseLength)
case fcWriteSingleRegister,
fcWriteMultipleRegisters,
fcWriteSingleCoil,
fcWriteMultipleCoils: byteCount = 3
case fcMaskWriteRegister: byteCount = 5
fcWriteMultipleCoils:
byteCount = 3
case fcMaskWriteRegister:
byteCount = 5
case fcReadHoldingRegisters | 0x80,
fcReadInputRegisters | 0x80,
fcReadCoils | 0x80,
@@ -236,8 +240,11 @@ func expectedResponseLenth(responseCode uint8, responseLength uint8) (byteCount
fcWriteMultipleRegisters | 0x80,
fcWriteSingleCoil | 0x80,
fcWriteMultipleCoils | 0x80,
fcMaskWriteRegister | 0x80: byteCount = 0
default: err = ErrProtocolError
fcMaskWriteRegister | 0x80,
0x41 | 0x80:
byteCount = 0
default:
err = ErrProtocolError
}
return