TMC211-PA20 TRINAMIC [TRINAMIC Motion Control GmbH & Co. KG.], TMC211-PA20 Datasheet - Page 28

• Manufacturer Part Number: TMC211-PA20
• Description: Micro Stepping Stepper Motor Controller / Driver with LIN Interface
• Manufacturer: TRINAMIC [TRINAMIC Motion Control GmbH & Co. KG.]

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6.8 Dynamic Assignment of LIN Identifiers
The identifier field in the LIN message frame denotes the content of the message. Six identifier bits
and two parity bits are used to represent the content. The identifiers 0x3C to 0x3F are reserved for
command frames and extended frames. Slave nodes need to be very flexible to adapt itself to a given
LIN network in order to avoid conflicts with slave nodes from different manufacturers. Dynamic
assignment of identifiers fulfills this requirement by writing identifiers into the circuits RAM. ROM
pointers are linking commands and dynamic identifiers together.
A writing frame with identifier 0x3C issued by the LIN master writes dynamic identifiers into the RAM.
One writing frame is able to assign 4 identifiers, therefore 3 frames are needed to assign all identifiers.
Each ROM pointer ROMp_x [3:0] places the corresponding dynamic identifier Dyn_ID_x [5:0] at the
correct place in the RAM, see table below. When setting <BROAD> to zero broadcasting is active and
each slave on the LIN bus will store the same dynamic identifiers, otherwise only the slave with the
corresponding slave address is programmed.
Byte
Copyright © 2004-2005 TRINAMIC Motion Control GmbH & Co. KG
0
1
2
3
4
5
6
7
8
Content
Identifier
AppCMD
CMD
Address
Data
Data
Data
Data
Data
Dynamic ID
user defined
user defined
user defined
user defined
user defined
user defined
user defined
user defined
user defined
Bit7
Figure 17: Principle of dynamic command assignment
Broad
ROMp_4 [1:0]
DynID_2 [1:0]
Dynamic assignment done at start-up
Command assignment via Dynamic ID during operation
1
Bit6
Dynamic Identifiers Writing Frame
AD6
ROMp_3 [3:0]
DynID_1 [3:0]
ROM pointer
(binary)
0000
0001
0010
0011
0100
0101
0110
0111
1000
Bit5
AD5
DynID_4 [5:0]
TMC211 DATASHEET (V. 1.04 / January 7, 2005)
Bit4
AD4
ROMp_2 [3:0]
Structure
0x3C
0x80
Application command
General purpose 2 data bytes
General purpose 4 data bytes
GetActualPosition
GetStatus
SetPosition (2 data bytes)
SetPositionShort (1 Motor)
SetPositionShort (2 Motors)
SetPositionShort (4 Motors)
Preparation frame
Bit3
0x11
AD3
DynID_3 [5:0]
Bit2
AD2
ROMp_1 [3:0]
DynID_2 [5:2]
Bit1
AD1
ROMp_4 [3:2]
DynID_1 [5:4]
Bit0
AD0