AK7401 Datasheet, PDF (11/29 Pages) Asahi Kasei Microsystems – Rotary Position Sensor IC

[AK7401]
15. Serial I/F Protocol
Figure 7 shows timing chart on serial interface protocol. Data communication is only available when the
CS pin set to “H”. To write the internal register or EEPROM, serial data must be input via the SIN/SOUT
pin on the falling edge of SCLK. To read the internal register or EEPROM, the AK7401 outputs serial
data on the rising edge of SCLK.
<Write>
CS
SCLK
1
2
3
4
5
6
7
8
9
10
11
12
13
14
22
23
24
Hi-Z
* ^SIN/SOUT
OP3 OP2 OP1 OP0 A6
A5
A4
A3
A2
A1
A0
*
D11 D10 D2
D1
D0
*
OPCODE(OP[3:0])：²OP[3:0]=0001bin
<Read>
CS
SCLK
1
2
3
4
5
6
10
11
12
13
14
15
16 20
21
22
23
24
SIN/SOUT _*
OP3 OP2 OP1
OP0 A6
A5
A1
A0
Ｈｉ-Ｚ D11 D10 D9
D8 D4
D3
D2
D1
D0
Hi-Z
OPCODE(OP[3:0])：OP[3:0]=0010bin
OPX:Operation Code
AX:Memory / Register Address
DX:Serial data
*:Don’t care
Figure 7. Serial I/F Timing Chart
● OPCODE
OPCODE
[3：0]
0000
0001
0010
0011
0100
0101
0110
0111
1000
1001
1010
1011
1100
1101
1110
1111
Table 4. Operation Code Description
Code name
Description
N/A
WriteEEPROM
ReadEEPROM
WriteReg
ReadReg
ChangeMode
Reset
N/A
N/A
ReadAngle
N/A
N/A
N/A
N/A
N/A
N/A
N/A
Stores data to EEPROM
Reads data from EEPROM
Stores data to the internal register
Reads the internal register data
Changes operating mode
Restarts the AK7401
N/A
N/A
Reads the angle data
N/A
N/A
N/A
N/A
N/A
N/A
Accessibility
Normal
User
Mode
Mode
invalid
invalid
invalid
valid
invalid
valid
invalid
valid
invalid
valid
valid
valid
invalid
valid
invalid
invalid
invalid
invalid
valid
valid
invalid
invalid
invalid
invalid
invalid
invalid
invalid
invalid
invalid
invalid
invalid
invalid
014002685-E-01
- 11 -
2015/07