FANOX SIL B, User Manual

Page: 236 / 311

www.fanox.com Rev.23 236/311
8.3. Exceptions and error responses
The error codes defined in the Modbus protocol are as follows:
01 ILLEGAL FUNCTION The slave does not support the function with function code specified in the
message received.
02 ILLEGAL DATA ADDRESS The master is attempting to execute an operation with an incorrect address.
03 ILLEGAL DATA VALUE The slave has detected that a value sent by the master is not valid.
04 SLAVE DEVICE FAILURE Indicates that an error has occurred in the slave while it was attempting to
execute the request received from the master.
05 ACKNOWLEDGE Generic recognition
06 SLAVE DEVICE BUSY The slave is busy and cannot execute the required operation.
07 NEGATIVE ACKNOWLEDGE Generic non-recognition
8.4. Data types
Type Length Description
UCHAR 1/2 Unsigned 1 byte
BYTE 1/2 Signed 1 byte integer
BIT16 1 Bit type in groups of 16.
Example: 0x1A41 = 0001101001000001b
BIT32 2 Bit type in groups of 32 in 32.
ENUM 1
Unsigned 16 bit integer. Each possible value of this integer has a corresponding
value in the auxiliary table of the database. This table shows the corresponding
string that should be shown for each value. Only an integer will be received into
memory.
Example: 0, 1 correspond to “CLOSED”, “OPEN”
DENUM 2 Unsigned 32 bit integer.
UINT 1 Unsigned two byte integer
INT 1 Signed two byte integer
LONG 2 Unsigned 4 byte integer
DWORD 2 Signed 4 byte integer
FLOAT 2 4 byte floating point number
ASCIIxx xx/2 String: Variable length string of characters. The end of the string is marked with
‘\0’
Example: “ABC” 0x41x42x43x00....
MILIS 3 Minutes (passed since 00:00 on 1/1/2000 (LONG). Milliseconds (UINT)