Beckhoff CX8050, Documentation

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CAN
CX8050, CX8051 - Embedded-PCs for
CANopen and CAN 121 Version: 1.4
1: Motorola format
k: Evaluation of complex terminals (analog and special terminals)
0: User data only (default)
1: Complete evaluation (note: analog channels then, for example, need 3 input and 3 output bytes instead of,
e.g., 2 input bytes; instead of 4 channels per PDO, 2 channels require a RxPDO and a TxPDO)
Bus Terminal / Extension Box register communication
Index Sub-index Name Type Attribute Mapping Default
value Meaning
0x4501 0 Access
Terminal
Register Unsigned8 ro N none Index
0x4501
allows
access to
all the
registers in
the bus
terminal or
extension
module.
Sub-index 0
contains
the number
of attached
bus
terminals.
1 Access
Reg.
Terminal 1 Unsigned32 rw N none Access to
bus
terminal or
extension
module
register 1
... ... ... ... ... ... ...
0XFE Access
Reg.
Terminal
254 Unsigned32 rw N none Access to
bus
terminal or
extension
module
register 254
The 32 bit value is composed as follows:
MSB LSB
Access (bit 7) + channel
number (bits 6...0) Register number High byte register value Low byte register value
[0..1] + [0...0x7F] [0...0xFF] [0...0xFF] [0...0xFF]
As is usual in CANopen, the LSB is transferred first, followed by the MSB.
Accessing index 0x4501 allows the user registers in the bus terminal or extension module to be written or
read. The modules have a set of registers for each input or output channel. The modules are addressed by
means of the sub-index; the channel number and register are addressed in the 32-bit data value. Channel
number 0 corresponds here to the first channel, 1 to the second channel, and so forth.