AMIS−30621
Table 55. SetPosition WRITING FRAME TYPE #4
Structure
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Byte
Content
Identifier
Data 1
0
1
2
3
4
5
6
7
8
9
0
0
1
1
1
1
0
0
AppCMD = 0x80
CMD[6:0] = 0x0B
AD1[6:0]
Pos1[15:8]
Pos1[7:0]
AD2[6:0]
Data 2
1
1
Data 3
Data 4
Data 5
Data 6
1
Data 7
Pos2[15:8]
Pos2[7:0]
Data 8
Checksum
Checksum over data
Where:
Adn[6:0]: Motor #n physical address (n ∈ [1,2]). Posn[15:0]: Signed 16−bit position set−point for motor #n.
SetPositionShort
implementing a maximum of 16 slave nodes. These 4 bits
are corresponding to the bits PA[3:0]in OTP memory. For
SetPositionShortoperation: It is recommended to set
HW0 and HW1 to ’1’. If the ADM bit is set to ’1’ the PA0
bit in OTP has to programmed to ’1’. If the ADM bit is set
to ’0’, HW2 has to be set to ’1’.
This command is provided to the circuit by the
LIN Master to drive one, two or four motors to a given
absolute position. It applies only for half stepping mode
(StepMode[1:0] = “00”) and is ignored when in other
stepping modes. See Positioning for more details.
The physical address is coded on 4 bits, hence
SetPositionShortcan only be used with a network
Two different cases must be considered, depending on the programmed value of the ADMbit in the OTP memory.
Bit PA0 in OTP
memory
ADM
AD[3]
Pin HW0
Pin HW1
Pin HW2
Tied to V
0
1
1
X
0
1
AD[0]
BB
Tied to GND
Tied to V
1
1
Tied to V
DD
BB
The priority encoder table (See Priority Encoder) describes the cases where a SetPositionShortcommand will be
ignored.
SetPositionShortcorresponds to the following LIN writing frames:
1. Two (2) data bytes frame for one (1) motor, with specific identifier (type #2)
Table 56. SetPositionShort WRITING FRAME TYPE #2
Structure
Bit 7
Bit 6
*
Bit 5
Bit 4
ID4
Bit 3
Bit 2
Bit 1
Bit 0
Byte
Content
Identifier
Data 1
0
1
2
3
*
0
ID3
ID2
ID1
ID0
Pos[10:8]
Broad
AD [3:0]
Data 2
Pos [7:0]
Checksum over data
Checksum
Where:
(*) According to parity computation
Broad: If broad = ‘0’ all the stepper motors connected to the LIN bus will go to Pos[10:0].
ID[5:0]: Dynamically allocated identifier to two data bytes SetPositionShortcommand.
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