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CP3BT26
26.5.8 Timer Interrupt Control Register (TICTL)
The TICTL register is a byte-wide, read/write register that
contains the interrupt enable bits and interrupt pending bits
for the four timer interrupt sources, designated A, B, C, and
D. The condition that causes each type of interrupt depends
on the operating mode, as shown in Table77.
This register is cleared upon reset. The register format is
shown below.
TAPND The Timer Interrupt Source A Pending bit indi-
cates that timer interrupt condition A has oc-
curred. For an explanation of interrupt
conditions A, B, C, and D, see Table 77. This
bit can be set by hardware or by software. To
clear this bit, software must use the Timer In-
terrupt Clear Register (TICLR). Attempting to
directly write a 0 to this bit is ignored.
0 – Interrupt source A has not triggered.
1 – Interrupt source A has triggered.
TBPND The Timer Interrupt Source B Pending bit indi-
cates that timer interrupt condition B has oc-
curred. For an explanation of interrupt
conditions A, B, C, and D, see Table 77. This
bit can be set by hardware or by software. To
clear this bit, software must use the Timer In-
terrupt Clear Register (TICLR). Attempting to
directly write a 0 to this bit is ignored.
0 – Interrupt source B has not triggered.
1 – Interrupt source B has triggered.
TCPND The Timer Interrupt Source C Pending bit in-
dicates that timer interrupt condition C has oc-
curred. For an explanation of interrupt
conditions A, B, C, and D, see Table 77. This
bit can be set by hardware or by software. To
clear this bit, software must use the Timer In-
terrupt Clear Register (TICLR). Attempting to
directly write a 0 to this bit is ignored.
0 – Interrupt source C has not triggered.
1 – Interrupt source C has tri ggered.
TDPND The Timer Interrupt Source D Pending bit in-
dicates that timer interrupt condition D has oc-
curred. For an explanation of interrupt
conditions A, B, C, and D, see Table 77. This
bit can be set by hardware or by software. To
clear this bit, software must use the Timer In-
terrupt Clear Register (TICLR). Attempting to
directly write a 0 to this bit is ignored.
0 – Interrupt source D has not triggered.
1 – Interrupt source D has tri ggered.
TAIEN The Timer Interrupt A Enable bit controls
whether an interrupt is generated on each oc-
currence of interrupt condition A. For an ex-
planation of interrupt conditions A, B, C, and
D, see Table77.
0 – Condition A interrupts disabled.
1 – Condition A interrupts enabled.
TBIEN The Timer Interrupt B Enable bit controls
whether an interrupt is generated on each oc-
currence of interrupt condition B. For an ex-
planation of interrupt conditions A, B, C, and
D, see Table77.
0 – Condition B interrupts disabled.
1 – Condition B interrupts enabled.
TCIEN The Timer Interrupt C Enable bit controls
whether an interrupt is generated on each oc-
currence of interrupt condition C. For an ex-
planation of interrupt conditions A, B, C, and
D, see Table77.
0 – Condition C interr upts disabled.
1 – Condition C interr upts enabled.
TDIEN The Timer Interrupt D Enable bit controls
whether an interrupt is generated on each oc-
currence of interrupt condition D. For an ex-
planation of interrupt conditions A, B, C, and
D, see Table77.
0 – Condition D interr upts disabled.
1 – Condition D interr upts enabled.
26.5.9 Timer Interrupt Clear Register (TICLR)
The TICLR register is a byte-wide, write-only register that al-
lows software to clear the TAPND, TBPND, TCPND, and
TDPND bits in the Timer Interrupt Control (TICTRL) regis-
ter. Do not modify this register with instructions that access
the register as a read-modify-write operand, such as the bit
manipulation instructions. The register reads as FFh. The
register format is shown below.
TACLR The Timer Pending A Clear bit is used to clear
the Timer Interrupt Source A Pending bit
(TAPND) in the Timer Interrupt Control regis-
ter (TICTL).
0 – Writing a 0 has no effect.
1 – Writing a 1 clears the TAPND bit.
TBCLR The Timer Pending A Clear bit is used to clear
the Timer Interrupt Source B Pending bit (TB-
PND) in the Timer Interrupt Control register
(TICTL).
0 – Writing a 0 has no effect.
1 – Writing a 1 clears the TBPND bit.
TCCLR The Timer Pending C Clear bit is used to clear
the Timer Interrupt Source C Pending bit
(TCPND) in the Timer Interrupt Control regis-
ter (TICTL).
0 – Writing a 0 has no effect.
1 – Writing a 1 clears the TCPND bit.
TDCLR The Timer Pending D Clear bit is used to clear
the Timer Interrupt Source D Pending bit (TD-
PND) in the Timer Interrupt Control register
(TICTL).
0 – Writing a 0 has no effect.
1 – Writing a 1 clears the TDPND bit.
7 6 5 4 3 2 1 0
TDIEN TCIEN TBIEN TAI EN TDPND TCPND TBPND TA PN D
7 4 3 2 1 0
Reserved TDCLR TCCLR TBCLR TAC LR