Fairbanks X SERIES PR 5220 ETHERNET TRANSMITTER - Manual (Page 83)

Section 7: Fieldbus Interface
05/11 84 51209 Revision 2
7.2.3 Reading and Writing Register via Fieldbus
7.2.4 Reading Data: Read_Value, Read_Value_Select, Read_Value_Selected
When the master has to read from the instrument, the register number is transmitted in
Read_Value_Select in the input area. The result is specified with Read_Value_Selected in the output
area .
Action of the master
Response of PR 5220
Writing register no. in Read_Value_Select
Writing the selected register in Read_Value
Copying Read_Value_Select into
Read_Value_Selected
Waiting, until
Read_Value_Selected = Read_Value_Select
Reading Read_Value
7.2.5 Writing Data: Write_Value, Write_Value_Select, Write_Active
When the master has to write into the instrument, the required action is transmitted into the input
area with
Write_Value_Select together with the data. Execution is indicated by bit Write_Active in the
output area.
Action of the master
Response of PR 5220
Writing value in Write_Value
Writing the register number in
Write_Value_Select
Writing Write_Value in the selected register
Setting bit Write_Active
Waiting, until Write_Active was set
Writing 0 in Write_Value_Select
Resetting bit Write_Active
7.2.6 Setting Bit: Action_Select, Write_Active
Single bits can be set or reset directly with Write_Value_Select .
For setting, the bit number (80.. 127) is written in Write_Value_Select .
For resetting, the bit number + 128 (208..255) is written in Write_Value_Select .
Action of the master
Response of PR 5220
Writing the register number in
Write_Value_Select
Writing Write_Value in the selected register
Setting bit Write_Active
Waiting, until Write_Active was set
Writing 0 in Write_Value_Select
Resetting bit Write_Active
7.2.7 Reading Bit
Single bits can be read only by reading a register. The procedure is described in Chapter 0.