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Device manual AS-i M4 Gateway Profibus DPV1 (AC1375, AC1376)
2012-02-23
DP module 12: extended command channel
Commands in the extended command channel
257
11.3.17
Module 12, extended command 35 (23hex) – write 7.4
parameter string of an AS-i slave
5752
Request from fieldbus master to device
Bit
Offset
Word no.
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
1
res.
S
M
UID
command number = 35
dec
= 23
hex
2
res. = 0
ST
SLA
res. = 0
DL
3
parameter byte 1
parameter byte 0
4...11
parameter bytes 2...17
12
parameter byte 19
parameter byte 18
13...18
not used
not used
Legend:
S
sequence bit
1 bit
a large data packet is transmitted in several partial sequences:
0 = data transmission completed
1 = data transmission not yet completed, at least one more packet follows
M
master no.
1 bit
0 = master 1
1 = master 2
UID
user ID
5 bits
00…1F
hex
= 0…31
dec
(a change to the user ID starts the command call)
ST
slave type
1 bit
0 = single slave or A slave
1 = B slave (= addition of 20
hex
or 32
dec
to the slave address)
SLA
slave address
5 bits
00…1F
hex
= 0…31
dec
DL
data length
5 bits
00…1F
hex
= 0…31
dec
NOTE
The number of the bytes to be sent must be divisible by 2 since the system always can transmit only
multiples of 2 bytes in the S7.4 protocol.
The control bytes defined in profile 7.4 with follow bit and valid bit are automatically added by the
system. Therefore, without segmentation, this command is limited to 20 bytes of parameter data. Larger
data volumes must be divided into several segments.
