HD404054 Datasheet, PDF (51/101 Pages) Hitachi Semiconductor – HMCS400-series microcomputers designed to increase program productivity with large-capacity memory

HD404054 Series/HD404094 Series
Registers for Timer C Operation: By using the following registers, timer C operation modes are selected
and the timer C count is read and written.
Timer mode register C1 (TMC1: $00D)
Timer mode register C2 (TMC2: $014)
Timer write register C (TWCL: $00E, TWCU: $00F)
Timer read register C (TRCL: $00E, TRCU: $00F)
• Timer mode register C1 (TMC1: $00D): Four-bit write-only register that selects the free-
running/reload timer function, input clock source, and the prescaler division ratio as shown in figure 34.
It is reset to $0 by MCU reset.
Writing to this register is valid from the second instruction execution cycle after the execution of the
previous timer mode register C1 write instruction. Setting timer C’s initialization by writing to timer
write register C (TWCL: $00E, TWCU: $00F) must be done after a mode change becomes valid.
Timer mode register C1 (TMC1: $00D)
Bit
Initial value
Read/Write
Bit name
3
0
W
TMC13
2
0
W
TMC12
1
0
W
TMC11
0
0
W
TMC10
TMC13
0
1
Free-running/reload timer selection
Free-running timer
Reload timer
TMC12 TMC11 TMC10
0
0
0
1
1
0
1
1
0
0
1
1
0
1
Input clock period
2048t_cyc
1024t_cyc
512t_cyc
128t_cyc
32t_cyc
8t_cyc
4t_cyc
2t_cyc
Figure 34 Timer Mode Register C1 (TMC1)
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