Freescale Semiconductor MC68HC908MR32, MC68HC908MR16 manual Tima Counter Modulo Registers

Timer Interface A (TIMA)

16.7.3 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 timer 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.

Register Name and Address:			TAMODH — $0011
	Bit 7	6	5	4	3	2	1	Bit 0
Read:
	Bit 15	Bit 14	Bit 13	Bit 12	Bit 11	Bit 10	Bit 9	Bit 8
Write:
Reset:	1	1	1	1	1	1	1	1
Register Name and Address:			TAMODL — $0012
	Bit 7	6	5	4	3	2	1	Bit 0
Read:
	Bit 7	Bit 6	Bit 5	Bit 4	Bit 3	Bit 2	Bit 1	Bit 0
Write:
Reset:	1	1	1	1	1	1	1	1

Figure 16-7. TIMA Counter Modulo Registers

(TAMODH and TAMODL)

NOTE

Reset the TIMA counter before writing to the TIMA counter modulo registers.

16.7.4 TIMA Channel Status and Control Registers

Each of the TIMA channel status and control registers:

•Flags input captures and output compares

•Enables input capture and output compare interrupts

•Selects input capture, output compare, or PWM operation

•Selects high, low, or toggling output on output compare

•Selects rising edge, falling edge, or any edge as the active input capture trigger

•Selects output toggling on TIMA overflow

•Selects 0 percent and 100 percent PWM duty cycle

•Selects buffered or unbuffered output compare/PWM operation

MC68HC908MR32 • MC68HC908MR16 Data Sheet, Rev. 6.1

228 Freescale Semiconductor