AMIS-30621 Datasheet, PDF (41/43 Pages) AMI SEMICONDUCTOR – LIN Microstepping Motordriver

AMIS-30621 LIN Microstepping Motordriver
Data Sheet
9.2.4.6.4 Dynamic Assignment of Identifiers
Apart from identifiers 0x3C to 0x3F, the LIN rev 1.2
specification does not indicate how identifiers can be
allocated. Therefore, slave nodes need to be flexible
enough to adapt themselves to a given LIN network.
One solution proposed by BMW is to implement a dynamic
assignment of the identifiers by the LIN Master. This is done
at start-up of the system by writing identifiers in the slave’s
RAM to make them correspond to commands pointers
located in the slave’s ROM. This is the strategy adopted for
the AMIS-30621.
Dynamic assignment must be done by a writing frame with
identifier 0x3C.
bit 7
0
bit 6
0
bit 5
1
1
Broad
AD6
AD5
ID1[3:0]
ID2[1:0]
ROMp3[3:0]
ROMp4[1:0]
ID4[5:0]
bit 4
bit 3
bit 2
bit 1
bit 0
1
1
1
0
0
AppCmd = 0x80
CMD[6:0] = 0x11
AD4
AD3
AD2
AD1
AD0
ROMp1[3:0]
ROMp2[3:0]
ID1[5:4]
ID2[5:2]
ID3[5:0]
ROMp4[3:2]
Identifier
Data1
Data2
Data3
Data4
Data5
Data6
Data7
Data8
With:
CMD[6:0] :
Broad
IDn[5:0] :
0x11, corresponding to dynamic assignment
of 4 LIN identifiers.
If Broad = ‘0’ all the circuits connected to the
LIN bus will share the same dynamically
assigned identifiers.
Dynamically assigned LIN identifier to the
application command which ROM pointer is
ROMpn[3:0] (see § 9.2.4.7).
One frame allows only to assign 4 identifiers. Therefore,
additional frames could be needed in order to assign more
identifiers (maximum 3 for the AMIS-30621).
9.2.4.7 Commands Table
Command Mnemonic
GetActualPos
GetFullStatus
GetOTPparam
GetStatus
GotoSecurePosition
HardStop
ResetPosition
ResetToDefault
RunInit
SetMotorParam
SetOTPparam
SetPosition (16-bit)
SetPositionShort (1 motor)
SetPositionShort (2 motors)
SetPositionShort (4 motors)
Sleep
SoftStop
Dynamic ID assignment
General purpose 2 Data bytes
General purpose 4 Data bytes
Preparation frame
Command Byte
(CMD)
000000 0x00
000001 0x01
000010 0x02
000011 0x03
000100 0x04
000101 0x05
000110 0x06
000111 0x07
001000 0x08
001001 0x09
010000 0x10
001011 0x0B
001100 0x0C
001101 0x0D
001110 0x0E
n.a. n.a.
001111 0x0F
010001 0x11
xxx allows to address physically a slave node. Therefore,
these dynamic IDs cannot be used for more than 8 stepper
motors.
Dynamic ID
(example)
100xxx
n.a.
n.a.
000xxx
n.a.
n.a.
n.a.
n.a.
n.a.
n.a.
n.a.
010xxx
001001
101001
111001
ROM Pointer
0010
0011
0100
0101
0110
0111
n.a.
n.a.
011000
101000
011010
0000
0001
1000
Only 9 ROM pointers are needed for the AMIS-30621.
AMI Semiconductor - Rev. 1.4
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