Chapter 4 Deployment CP 343-2P ASI
Manual VIPA System 300V
4-10
HB130E - CP - RE_343-2AH10 - Rev. 08/41
Data transfer with the user program
Depending on the slave type there are the following possibilities for access
from the user program:
Access to ...
Type A/B
(standard)
Type A
Type B
binary data
Peripheral load and transfer instructions
X
X
SFC 58/59 (read/write: Record set 150)
X
-
X
analog data
SFC 58/59 (read/write: Record set 140...147)
X
-
-
Each AS-i A/B-(standard) or A slave is assigned four bits "nibble" by the
AS-i master. This nibble may be accessed by the user program by means
of peripheral load and transfer instructions as e.g.:
L PIW x
(Access to slave input data)
L PID x
T PQW x
(Access to slave output data)
T PQD x
with x byte address in AS-i master CP
Please regard that the input nibbles of the AS-i analog slaves are set to "0"
in the process image of the CP. The CP ignores the output nibbles.
Note!
For system internal reasons the access to even byte addresses is only
allowed in words or double words. Byte transfer operations are not allowed.
Backplane bus
AS-i bus
AS-i
slave 1
AS-i
slave 2
AS-i
slave 31
.
.
.
AS-i master
CPU
I/O load command
I/O transfer command
Standard / A slaves
Overview
Access to binary
data at
A/B-(Standard) /
A slave
