User Manual 08/2003 Edition

4
4 Communications via PROFIBUS DP 02.99 02.00
4.3 Parameter area (PKW area)
4.3.2 Example: Reading parameters via PROFIBUS
Example:
Reading
parameters via
PROFIBUS
What is
programmed on
the master side?
4-116
It at least one fault is present, the drive fault buffer (P947) should be
read out and buffered on the master side.
Assumptions for the slave:
The drive has been completely commissioned, is
connected to PROFIBUS DP and is ready.
PROFIBUS node address = 12
Assumptions for the master:
The DP master is a SIMATIC S7 (CPU: S7-315-2-DP)
Hardware configuration
– Node address = 12
– Part I address O address
PKW 256 – 263 256 – 263
PZD 264 – 267 264 – 267 (not drawn in the example)
If the input signal from the peripheral area (I/O area) I265.3 (ZSW1.3,
fault present/no fault present) has a ”1” signal, then the following must
be executed on the master side (refer to Fig.4-7):
1. Programming SFC14 and SFC15
The standard functions SFC14 ”Read slave data” and SFC15 ”write
slave data” are required in order to consistently transfer more than 4
bytes.
2. Request parameter value
– Write into the PKW output signals (AB 256 – 263)
with
AK = 1, PNU = 947, IND = 0, PWE = no significance
3. Read parameter value and save
– Evaluate the PKW input signals (EB 256 – 263)
– If AK = 1, PNU = 947, IND = 0 and PWE = xx
––> then O. K.
––> read P947 = xx and buffer
– If AK = 7,
––> then not O. K.
––> evaluate the fault number in EW 262
(refer to Table 4-15)
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SIMODRIVE POSMO A User Manual (POS1) – 08.03 Edition