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/Event Counter 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 devices contains several external
interrupt and internal interrupts functions. The external interrupt is generated by the action of the
external INT pin, while the internal interrupts are generated by various internal functions such as the
Touch Keys, Timer/Event Counter, Time Base, SIM etc.
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 depends upon the device chosen but fall into three
categories. The first is the INTC0~INTC3 registers which setup the primary interrupts, the second is
the MFI0~MFI2 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.
Function
Enable Bit
Request Flag
Notes
Global
EMI
¾
¾
INT Pin
INTE
INTF
¾
Touch Key Module
TKMnE
TKMnF
n=0~5
SIM
SIME
SIMF
EEPROM
DEE
DEF
Multi-function
MFnE
MFnF
n=0~2
Time Base
TBE
TBF
¾
Timer/Event Counter
TnE, TE
TnF, TF
n=0~1
Touch Key Module 16-bit Counter
Mn16CTE
Mn16CTF
n=0~5
Interrupt Register Bit Naming Conventions
Rev. 1.50
96
April 28, 2020
BS83B08-3/B12-3/B16-3/B16G-3/C24-3
8-Bit Touch Key Flash MCU