STMPE2403 Datasheet, PDF (57/63 Pages) STMicroelectronics – 24-bit Enhanced port expander with Keypad and PWM controller Xpander logic

STMPE2403
Rotator controller
Figure 13. Registers for rotator control
Address
Register name
0x70
Rotator_Control
0x72
Rotator_Buffer
Rotator_Control
Register size
8
8
Bit
7
6
5
4
3
2
1
0
Start_FSM Reserved
Read/Write
RW
R
R
R
R
R
R
R
Reset Value
0
0
0
0
0
0
0
0
Table 57. Bit description
Bits
Name
Description
7
Start_FSM Rotator FSM start bit.
‘1’ – Activate the FSM
‘0’ – Stop sampling rotator symbols
Rotator_Buffer
Bit
7
6
5
4
3
2
1
0
Symbol_Type
Symbol_Count
Read/Write
R
R
R
R
R
R
R
R
Reset Value
0
0
0
0
0
0
0
0
Table 58. Bit description
Bits
Name
Description
7
Symbol_Type Symbol type to be reported
‘1’ – Down
‘0’ – Up
6~0
Symbol_Count Number of symbols of the type specified by bit 7
Minimum of 0 (b’0000000) to
Maximum of 127 (b’1111111)
The host should do the following on the I2C bus to start the Rotator controller:
1. The host writes to GPIO Controller to select the Rotator Bits on the relevant IO.
2. Write Rotator_Control data register to start the rotator controller. A maximum of 2
rotations later, the correct initial state on the rotator FSM is obtained. Scanning for
rotator movement continues.
3. The host waits for interrupt from the rotator controller.
4. The host reads Rotator_Buffer
5. The host can stop rotator controller operation by writing to Rotator_Control register.
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