STMPE2401 datasheet(47/55 Pages) STMICROELECTRONICS

Part #	STMPE2401

Description	24-bit Enhanced port expander with Keypad and PWM controller Xpander logic

PDF	55 Pages

Scroll/Zoom	100%

Manufacturer	STMICROELECTRONICS [STMicroelectronics]

Direct Link	http://www.st.com

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47 / 55 page

STMPE2401

Rotator controller

47/55

Rotator controller

Rotator controller consists of 3 terminal, each capable of becoming an input with internal

pull-up, or and output. At any moment, 2 terminals are inputs and one terminal is output.

Figure 10. Rotator controller

The Rotator Controller is responsible for the detection of the direction of rotator and the

reporting of these direction sequences. The direction of a rotator can be either up or down.

A rotator has 3 contacts and detection of shorts on these contacts is used to determine the

direction of rotation. Following diagram shows the definition of the direction of rotation and

how the FSM states and driven outputs correspond to rotation.

Figure 11. Possible conditions

Table 46. 3 possible conditions: A-B short, B-C short, C-A short.

Input

Current State

Next State

Result

State

Output

Input

State

Output

Input

Down

STMPE2401 Datasheet(PDF) 47 Page - STMicroelectronics