Motorola MC68HC908AB32 - TIMA Counter Modulo Registers

Timer Interface Module A (TIMA)
I/O Registers
MC68HC908AB32 — Rev. 1.0 Technical Data
MOTOROLA Timer Interface Module A (TIMA) 187
11.10.3 TIMA Counter Modulo Registers
The read/write TIMA modulo registers contain the modulo value for the
TIMA counter. When the TIMA counter reaches the modulo value, the
overflow flag (TOF) becomes set, and the TIMA counter resumes
counting from $0000 at the next clock. Writing to the high byte
(TAMODH) inhibits the TOF bit and overflow interrupts until the low byte
(TAMODL) is written. Reset sets the TIMA counter modulo registers.
NOTE: Reset the TIMA counter before writing to the TIMA counter modulo
registers.
Address: $0023
Bit 7 654321Bit 0
Read: Bit 7 654321Bit 0
Write:
Reset: 00000000
= Unimplemented
Figure 11-6. TIMA Counter Register Low (TACNTL)
Address: $0024
Bit 7 654321Bit 0
Read:
Bit 15 14 13 12 11 10 9 Bit 8
Write:
Reset: 11111111
Figure 11-7. TIMA Counter Modulo Register High (TAMODH)
Address: $0025
Bit 7 654321Bit 0
Read:
Bit 7 654321Bit 0
Write:
Reset: 11111111
Figure 11-8. TIMA Counter Modulo Register Low (TAMODL)