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Micro-Graphic Panel Error Code Table (cont’d)
Modbus Protocols Error Code P499 Explanation
The following table lists the errors that can be generated by the Modbus protocols:
AutomationDirect CLICK
AutomationDirect DirectLOGIC - Modbus (Koyo)
Modicon Modbus RTU
Entivity Modbus RTU
Note:
The following errors can be generated from the designated PLC, are monitored by the
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Micro-
Graphic panel, and displayed on the panel’s screen as a hexadecimal value in panel error code P499, if active.
EA1-TCL-M Hardware User Manual, 2nd Ed., 10/10
®
A
Appendix A: Panel & PLC Error Code Tables
A–4
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Micro-Graphic Panel Error Table (cont’d)
Error Code
Error Message
Cause
P499*
ErrCode Received ->
Recv .Err Code XXXX
A PLC generated error code with a hexadecimal value of XXXX has been returned from the
PLC. * See the explanation for error code P499 proceeding each set of PLC error code tables.
P500
Can'tWriteS.Port
Data cannot be written to the Serial port.
Data was sent to the PLC via the Serial Port.
If this error shows on the Panel, it indicates a Hardware Problem.
P700
RD.Buff.MEM Full
There was an error while allocating memory for the read buffer. When this error is displayed, a
memory leak may have occurred.
P701
INV.PLC Address
Request to inaccessible memory from the HMI layer to the PLC protocol layer. This error is an
indication that there is a problem in the HMI layer.
P702
INV.FUN.Code
A Read/Write/SetBit request has been sent to an invalid memory area. This error is an
indication that there is a problem in the HMI layer.
P703
WRT.PLC.ReadOnly
A PLC Write request was made to the PLC’s Read-Only memory area.This error is an indication
that there is a problem in the HMI layer or the PLC protocol layer.
PLC Error Codes Modbus Protocols
Panel Error Code
P499 Hex Value
Name
Meaning
0x0001
ILLEGAL
FUNCTION
The function code received in the query is not an allowable action for the server (or slave). This
may be because the function code is only applicable to newer devices and was not
implemented in the unit selected. It could also indicate that the server (or slave) is in the wrong
state to process a request of this type, for example because it is unconfigured and is being
asked to return registered values.
0x0002
ILLEGAL DATA
ADDRESS
The data address received in the query is not an allowable address for the server (or slave).
More specifically, the combination of reference number and transfer length is invalid. For a
controller with 100 registers, the PDU addresses the first register as 0, and the last one as 99.
If a request is submitted with a starting register address of 96 and a quantity of registers of 4,
then the request will successfully operate (address-wise at least) on registers 96, 97, 98, 99. If
a request is submitted with a starting register of 96 and a quantity of registers of 5, then the
request will fail with Exception code 0x02 "Illegal Data Address" since it attempts to operate on
registers 96, 97, 98, 99 and 100, and there is no register with address 100.
0x0003
ILLEGAL DATA
VALUE
A value contained in the query data field is not an allowable value for server (or slave). This
indicates a fault in the structure of the remainder of a complex request, such as that the implied
length is incorrect. It specifically does NOT mean that a data item submitted for storage in a
register has a value outside the expectation of the application program, since the Modbus
protocol is unaware of the significance of any particular value of any particular register.
0x0004
SLAVE DEVICE
FAILURE
An unrecoverable error occurred while the server (or slave) was attempting to perform the
requested action.
