Motorola MC68HC908MR32 사용자 설명서
Advance Information
MC68HC908MR16/MC68HC908MR32 — Rev. 4.0
214
Timer Interface A (TIMA)
MOTOROLA
Timer Interface A (TIMA)
11.8 I/O Registers
These input/output (I/O) registers control and monitor TIMA operation:
•
TIMA status and control register (TASC)
•
TIMA control registers (TACNTH–TACNTL)
•
TIMA counter modulo registers (TAMODH–TAMODL)
•
TIMA channel status and control registers (TASC0, TASC1,
TASC2, and TASC3)
TASC2, and TASC3)
•
TIMA channel registers (TACH0H–TACH0L, TACH1H–TACH1L,
TACH2H–TACH2L, and TACH3H–TACH3L)
TACH2H–TACH2L, and TACH3H–TACH3L)
11.8.1 TIMA Status and Control Register
The TIMA status and control register:
•
Enables TIMA overflow interrupts
•
Flags TIMA overflows
•
Stops the TIMA counter
•
Resets the TIMA counter
•
Prescales the TIMA counter clock
TOF — TIMA Overflow Flag
This read/write flag is set when the TIMA counter resets to $0000 after
reaching the modulo value programmed in the TIMA counter modulo
registers. Clear TOF by reading the TIMA status and control register
when TOF is set and then writing a logic 0 to TOF. If another TIMA
overflow occurs before the clearing sequence is complete, then
reaching the modulo value programmed in the TIMA counter modulo
registers. Clear TOF by reading the TIMA status and control register
when TOF is set and then writing a logic 0 to TOF. If another TIMA
overflow occurs before the clearing sequence is complete, then
Address: $000E
Bit 7
6
5
4
3
2
1
Bit 0
Read:
TOF
TOIE
TSTOP
0
0
PS2
PS1
PS0
Write:
0
TRST
R
Reset:
0
0
1
0
0
0
0
0
R
= Reserved
Figure 11-4. TIMA Status and Control Register (TASC)