Rockwell Automation RECOMM-PBUS PROFIBUS Communications Module - Manual (Page 80)

7-6 PROFIBUS Communications Module
7.3.3 Parameter Protocol Examples
Read Examples
Request Response
RC
Set to “1” (‘0001’) binary to read
RC
“1” (‘0001’) Transferring 8-bit or 16-bit parameter
value
“2” (‘0010’) Transferring a 32-bit parameter value
“7” (‘0111’) Request rejected (including fault code)
SPM
Not used SPM
Not used
PNU
Parameter number to read PNU
Confirms the Parameter number (if successful,
equals the PNU from the request)
Subindex
Selects which DPI port to talk to (“0” =
DPI Host, “5” = RECOMM-PBUS on
SP600 drives). Subindex
Confirms the DPI port (if successful, equals the
Subindex from the request)
Not Used Parameter value high word
Contains a “0” if returning a value from a 16-bit
parameter and the high word from a 32-bit
parameter
Not Used Parameter value low word
Contains the value from a 8-bit or 16-bit parameter,
the low word if reading from a 32-bit parameter, or
the fault code (if RC = “7”)
Bit 15-12 11 10-0 15-12 11 10-0
Parameter Access
Word 1 (PCA)
RC SPM PNU RC SPM PNU
Parameter Access
Word 2 (IND)
Subindex Subindex
Parameter Access
Word 3 (PVA)
Not Used Parameter value high
(32-bit high word)
Parameter Access
Word 4 (PVA)
Not Used Parameter value low
(32-bit low word/ or
8-bit/16-bit value)
Request
Response