Interrupts; Interrupt Registers - Holtek BS83A04C Manual

BS83A04C
4-Key Enhanced Touch I/O Flash MCU

Interrupts

Interrupts are an important part of any microcontroller system. When an external event or an internal
function such as a Touch action or Timer Module overflow requires microcontroller attention, their
corresponding interrupt will enforce a temporary suspension of the main program allowing the
microcontroller to direct attention to their respective needs. The device contains several external
interrupt and internal interrupt functions. The external interrupts are generated by the action of the
external INT pin, while the internal interrupts are generated by various internal functions such as the
Touch Keys, TM, Time Base and I

Interrupt Registers

Overall interrupt control, which basically means the setting of request flags when certain
microcontroller conditions occur and the setting of interrupt enable bits by the application program,
is controlled by a series of registers, located in the Special Purpose Data Memory, as shown
in the accompanying table. The number of registers falls into three categories. The first is the
INTC0~INTC1 registers which setup the primary interrupts, the second is the MFI0~MFI1 registers
which setup the Multi-function interrupts. Finally there is an INTEG register to setup the external
interrupt trigger edge type.
Each register contains a number of enable bits to enable or disable individual registers as well as
interrupt flags to indicate the presence of an interrupt request. The naming convention of these
follows a specific pattern. First is listed an abbreviated interrupt type, then the (optional) number of
that interrupt followed by either an "E" for enable/disable bit or "F" for request flag.
Global
INT Pin
I C
2
Time Base
Multi-function
Touch key TKRCOV
Touch key threshold TKTH
CTM
Register
Name
7
INTEG —
INTC0 —
INTC1 —
MFI0 —
MFI1 —
Rev. 1.00
C etc.
2
Function Enable Bit
EMI
INTE
I2CE
TBE
MFnE
TKRCOVE
TKTHE
CTMPE
CTMAE
Interrupt Register Bit Naming Conventions
6 5 4
— — —
MF1F MF0F INTF
— TBF I2CF
— TKTHF TKRCOVF
— CTMAF CTMPF
Interrupt Register List
89
Request Flag Notes
— —
INTF —
I2CF —
TBF —
MFnF n=0~1
TKRCOVF —
TKTHF —
CTMPF —
CTMAF —
Bit
3 2 1
— — INTS1
MF1E MF0E INTE
— — TBE
— — TKTHE
— — CTMAE
0
INTS0
EMI
I2CE
TKRCOVE
CTMPE
March 24, 2020