Touch Key Scan Operation Flowchart - Holtek HT32F54231 User Manual

32-Bit Arm ® Cortex ® -M0+ MCU
HT32F54231/HT32F54241/HT32F54243/HT32F54253
Figure 200. Touch Key Interrupts

Touch Key Scan Operation Flowchart

Figure 201. Touch Key Manual Scan Mode Flowchart – TKMOD[1:0] = 01
Rev. 1.00
Touch Key
MnK0THF
MnK0THS
MnK1THF
MnK1THS
MnK2THF
MnK2THS
MnK3THF
MnK3THS
TKRCOV
Touch Key Manual Scan Operation Start
Time Slot &
TKRCOV = 0
16-bit C/F Counter
keep counting
551 of 576
Interrupt Controller
TKTHINT
TKTHE
TKTHE
TKINT
TKRCOVE
TKRCOVE
Start
Write Ref. OSC Capacitor
value to TKMnROCPR
Set Start bit TKST 0 → 1
→ Busy flag TKBUSY = 1
Initiate Time Slot &
16-bit C/F Counter
All Time Slot &
16-bit C/F Counter
start to count
All Time Slot
Counter overflow ?
TKRCOV = 1
Touch key busy flag
TKBUSY = 0
Generate Interrupt request flag
Read C/F counter value from
TKMnCFCNTR
Touch key scan end
Set TKST 1 → 0
End
January 28, 2022