Process Image - WAGO I/OSYSTEM 750 Series Manual

2.1.3.7 Process Image

Using the I/O module 750-637/000-002, a 6 byte input and output process
image can be transferred to the fieldbus coupler / controller via two logical
channels.
The set values are stored in 4 output bytes (D0, D1, D2, D3) and the process
data are stored in 4 input bytes (D0, D1, D2, D3). Two control bytes (C0, C1)
and two status bytes (S0, S1) are used to select process data and set values as
well as to control the data flow.
Attention
The representation of the process data of some I/O modules or their variations
in the process image depends on the fieldbus coupler/-controller used. Please
take this information as well as the particular design of the respective
control/status bytes from the section "Fieldbus Specific Design of the Process
Data" included in the description concerning the process image of the
corresponding coupler/controller.
S0
D0
D1
S1
D2
D3
Bit 0 and bit 1 in the control byte C1 determines the process data.
 Counter value
 Latch value
 Velocity
 Set value
The setting is mirrored in status byte S1 in bit 0 and bit 1.
Bit 1
WAGO-I/O-SYSTEM 750
I/O Modules
Input data
Status byte S0
Process data byte 0 (LSB)
Process data byte 1
Status byte S1
Process data byte 2
Process data byte 3 (MSB)
MapPZD (Control Byte C1 / Status Byte S1, Bit 0 and 1)
Bit 0 Coding of the Process data
0 0 Counter value
0 1 Latch value
1 0 Velocity (Increments per milliseconds)
1 1 Set value
750-637/000-002 [Inc.Enc./24V/32Bit/S.E.]
Output data
C0 Control byte C0
D0 Set value byte 0 (LSB)
D1 Set value byte 1
C1 Control byte C1
D2 Set value byte 2
D3 Set value byte 3 (MSB)
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Process Image