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CHAPTER 9 8-BIT TIMER/EVENT COUNTERS 1 AND 2
(1) Compare registers 10 and 20 (CR10, CR20)
These are 8-bit registers to compare the value set to CR10 to the 8-bit timer register 1 (TM1) count value,
and the value set to CR20 to the 8-bit timer register 2 (TM2) count value, and, if they match, generate an
interrupt request (INTTM1 and INTTM2, respectively).
This register can also be used as the register which holds the interval time when setting TM1 and TM2 to interval
timer operation.
CR10 and CR20 are set with an 8-bit memory manipulation instruction. They cannot be set with a 16-bit
memory manipulation instruction. When the compare register is used as 8-bit timer/event counter, the 00H
to FFH values can be set. When the compare register is used as 16-bit timer/event counter, the 0000H to
FFFFH values can be set.
RESET input makes CR10 and CR20 undefined.
Caution When using the compare register as 16-bit timer/event counter, be sure to set data after
stopping timer operation.
(2) 8-bit timer registers 1, 2 (TM1, TM2)
These are 8-bit registers to count count pulses.
When TM1 and TM2 are used in the 8-bit timer × 2-channel mode, they are read with an 8-bit memory
manipulation instruction. When TM1 and TM2 are used as 16-bit timer × 1-channel mode, 16-bit timer (TMS)
is read with a 16-bit memory manipulation instruction.
RESET input sets TM1 and TM2 to 00H.
9.3 8-Bit Timer/Event Counters 1 and 2 Control Registers
The following four types of registers are used to control the 8-bit timer/event counter.
• Timer clock select register 1 (TCL1)
• 8-bit timer mode control register 1 (TMC1)
• 8-bit timer output control register (TOC1)
• Port mode register 3 (PM3)
(1) Timer clock select register 1 (TCL1)
This register sets count clocks of 8-bit timer registers 1 and 2.
TCL1 is set with an 8-bit memory manipulation instruction.
RESET input sets TCL1 to 00H.