Mitsubishi 2404f User Manual page 17

2408 f & 2404 f PROFIBUS Communications Handbook
THE COMMAND CODE AND TAG ARE ENCODED INTO REGISTER 1 AS FOLLOWS:
Bits 15-12
Command Code Reserved
Because only 11 bits are available for the Parameter Tag, the maximum tag allowable for standard demand data operations is
2048. The 2400 f series controller allows tag values of up to 16383, therefore, extended tags have been provided using register
2. This is particularly important if ramp/dwell programs or configuration information is to be transferred over PROFIBUS-DP.
Fields in a request (output registers) should be set as follows:
Command (Hex) Request (Master to Slave)
0
000
1
000
2
000
3 Extended Read Request
000
4 Extended Write Request
000
Valid responses to a given command are as follows:
Command Command
Field in request Field in response
(output register) (input register)
0
000
1
000
1
000
2
000
2
000
3
000
3
000
4
000
4
000
The command field in the response message either
Confirms that no operation has been requested
Indicates that a Read or Write request has been completed successfully
Indicates that a Read or Write has failed.
Error Codes in input register 4 are as follows.
Error Code
0
1
2
2408 f and 2404 f PROFIBUS Communications Handbook
Bit 11 Bit 10 - 0
Parameter Tag
Parameter Tag
No Command
Read Request
Write Request
0 Acknowledge No Command
000
1 Tag Read Successfully
000
7 Tag Read Not Successful
000
1 Tag Written Successfully
000
7 Tag Write Not Successful
000
1 Extended Tag Read Successfully
000
7 Extended Tag Read Not Successful
000
1 Extended Tag Written Successfully
000
7 Extended Tag Write Not Successful
000
Meaning
Invalid Tag Number
Read Only Parameter
Value out of range
NB: Eurotherm Extensions are printed in bold italic text
Extended
Parameter Tag
- -
Tag to Read -
Tag to Write -
Must be Zero Tag to Read
Must be Zero Tag to Write
Meaning
Demand Data
Value
-
-
Value to write
-
Value to Write
Returned Value
(input register 4)
-
Value Read
Error Code (see below)
-
Write Request
Value Read
Error Code (see below)
-
Error Code (see below)
7-3