HD404669 Datasheet, PDF (65/142 Pages) Hitachi Semiconductor – Low-Voltage AS Microcomputers with On-Chip DTMF Generation Circuit

HD404669 Series
Timer mode register C2 (TMC2: $014): Timer mode register C2 (TMC2: $014) is a 3-bit read/write
register, used to switch the function of the R31/TOC pin and select the timer C output mode as shown in
figure 44.
Timer mode register C2 (TMC2: $014) is reset to $0 by an MCU reset or in stop mode.
Timer mode register C2 (TMC2: $014)
Bit
Initial value
Read/Write
Bit name
3
2
—
0
—
R/W
Not used TMC22
1
0
R/W
TMC21
0
0
R/W
TMC20
TMC22 TMC21 TMC20
0
0
0
1
1
0
1
1
0
0
1
1
0
1
R3₁/TOC mode selection
R3₁
R3₁ port
TOC Toggle output
TOC 0 output
TOC 1 output
—
Not used
TOC PWM output
Figure 44 Timer Mode Register C2 (TMC2)
Timer write register C (TWCL: $00E, TWCU: $00F): Timer write register C (TWCL: $00E, TWCU:
$00F) is a write-only register composed of a lower digit (TWCL: $00E) and an upper digit (TWCU: $00F).
The lower digit (TWCL) of timer write register C is reset to $0 by an MCU reset or in stop mode, while the
upper digit (TWCU) is undetermined.
Timer C can be initialized by writing to timer write register C (TWCL, TWCU). To write the data, first
write the lower digit (TWCL). The lower digit write does not change the timer C value. Next, write the
upper digit (TWCU). Timer C is then initialized to the timer write register C (TWCL, TWCU) value.
When writing to timer write register C (TWCL, TWCU) from the second time onward, if it is not necessary
to change the lower digit (TWCL) reload value, timer C initialization is completed by the upper digit write
alone.
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