
Rev. 1.00
120
October 26, 2018
Rev. 1.00
121
October 26, 2018
BS86DH12C
High Voltage Touch A/D Flash MCU with HVIO
BS86DH12C
High Voltage Touch A/D Flash MCU with HVIO
timer counter will be automatically switched off when the time slot counter overflows. The clock
source for the time slot counter is sourced from the reference oscillator or f
SYS
/4 which is selected
using the MnTSS bit in the TKMnC1 register. The reference oscillator and key oscillator will be
enabled by setting the MnROEN bit and MnKOEN bits in the TKMnC1 register.
When the time slot counter in all the touch key modules or in the touch key module 0 overflows,
an actual touch key interrupt will take place. The touch keys mentioned here are the keys which are
enabled.
Each touch key module consists of four touch keys, KEY1~KEY4 are contained in module 0,
KEY5~KEY8 are contained in module 1, KEY9~KEY12 are contained in module 2. Each touch key
module has an identical structure.
Touch Key Interrupt
The touch key only has a single interrupt, when the time slot counter in all the touch key modules
or in the touch key module 0 overflows, an actual touch key interrupt will take place. The touch
keys mentioned here are the keys which are enabled. The 16-bit C/F counter, 16-bit counter, 5-bit
time slot unit period counter and 8-bit time slot counter in all modules will be automatically cleared.
More details regarding the touch key interrupt is located in the interrupt section of the datasheet.
Programming Considerations
After the relevant registers are set, the touch key detection process is initiated by changing the TKST
bit from low to high. This will enable and synchronise all relevant oscillators. The TKRCOV flag
which is the time slot counter flag will go high when the counter overflows. When this happens an
interrupt signal will be generated. As the TKRCOV flag will not be automatically cleared, it has to
be cleared by the application program.
The TKCFOV flag which is the 16-bit C/F counter overflow flag will go high when any of the Touch
Key Module 16-bit C/F counter overflows. As this flag will not be automatically cleared, it has to be
cleared by the application program. The TK16OV flag which is the 16-bit counter overflow flag will
go high when the 16-bit counter overflows. As this flag will not be automatically cleared, it has to be
cleared by the application program.
When the external touch key size and layout are defined, their related capacitances will then
determine the sensor oscillator frequency.