AMIS-30621 Datasheet, PDF (28/43 Pages) AMI SEMICONDUCTOR – LIN Microstepping Motordriver

AMIS-30621 LIN Microstepping Motordriver
Data Sheet
SetPositionShort()
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 § 8.5 for more details.
The physical address is coded on 4 bits, hence
SetPositionShort can only be used with a network
implementing a maximum of 16 slave nodes. These 4 bits
are normally corresponding to the bits PA[3:0] in OTP
memory (address 0x00), while bits AD[6:4] must be at ‘1’.
Two different cases must in fact be considered, depending
on the programmed value of bit ADM in the OTP memory
(see § 9.2.4.5):
ADM
0
1
1
AD[3]
X
0
1
pin HW0
pin HW1
Tied to Vdd
pin HW2
Tied to Vbb
Tied to Gnd
Tied to Vbat
bit PA0 in OTP memory
AD[0]
1
1
The priority encoder table (§ 9.2.2.12) acknowledges the
cases where a SetPositionShort command will be
ignored.
SetPositionShort corresponds to the following LIN
writing frames.
1) 2 Data bytes frame for 1 motor, with specific identifier (type #2)
bit 7
*
bit 6
*
Pos[10:8]
bit 5
0
bit 4
bit 3
ID4
ID3
Broad
Pos[7:0]
bit 2
bit 1
ID2
ID1
AD[3:0]
bit 0
ID0
Identifier
Data1
Data2
*) according to parity computation
SetPositionShort command.
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 2
Data bytes
2) 4 Data bytes frame for two motors, with specific identifier (type # 2)
bit 7
*
bit 6
*
Pos1[10:8]
bit 5
1
1
Pos2[10:8] 1
bit 4
bit 3
bit 2
0
ID3
ID2
AD1[3:0]
Pos1[7:0]
AD2[3:0]
Pos2[7:0]
*) according to parity computation
bit 1
ID1
bit 0
ID0
Identifier
Data1
Data2
Data3
Data4
ID[5:0] : Dynamically allocated identifier to 4 Data
bytes SetPositionShort command.
ADn[3:0] : Motor #n physical address least significant
bits (n ∈ [1,2]).
Posn[10:0] : Signed 11-bit position set point for Motor #n
3) 8 Data bytes frame for 4 motors, with specific identifier (type #2)
bit 7
*
bit 6
*
Pos1[10:8]
bit 5
1
Pos2[10:8]
Pos3[10:8]
Pos4[10:8]
bit 4
bit 3
1
ID3
1
Pos1[7:0]
1
Pos2[7:0]
1
Pos3[7:0]
1
Pos4[7:0]
bit 2
bit 1
ID2
ID1
AD1[3:0]
AD2[3:0]
AD3[3:0]
AD4[3:0]
bit 0
ID0
Identifier
Data1
Data2
Data3
Data4
Data5
Data6
Data7
Data8
*) according to parity computation
ID[5:0] :
Dynamically allocated identifier to 8 Data
bytes SetPositionShort command.
AMI Semiconductor - Rev. 1.4
www.amis.com
ADn[3:0] : Motor #n physical address least significant
bits (n ∈ [1,4]).
Posn[10:0] : Signed 11-bit position set point for Motor #n
(see § 0).
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