HD404629R Datasheet, PDF (79/157 Pages) Renesas Technology Corp – AS Microcomputer Incorporating a DTMF Generator Circuit

HD404629R Series
 Port mode register C (PMRC: $025)
 Detection edge select register 2 (ESR2: $027)
• Timer mode register D1 (TMD1: $010): 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 63. 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 D1 (TMD1: $010) write instruction. Setting timer D’s initialization by
writing to timer write register D (TWDL: $011, TWDU: $012) must be done after a mode change
becomes valid.
When selecting the input capture timer operation, select the internal clock as the input clock source.
Timer mode register D1 (TMD1: $010)
Bit
Initial value
Read/Write
Bit name
3
0
W
TMD13
2
0
W
TMD12
1
0
W
TMD11
0
0
W
TMD10
TMD13
0
1
Free-running/reload timer selection TMD12 TMD11 TMD10
Free-running timer
Reload timer
0
0
0
1
1
0
1
1
0
0
1
1
0
1
Input clock period and
input clock source
2048t_cyc
512t_cyc
128t_cyc
32t_cyc
8t_cyc
4t_cyc
2t_cyc
R2₀/EVND
(external event input)
Figure 63 Timer Mode Register D1 (TMD1)
• Timer mode register D2 (TMD2: $015): Four-bit read/write register that selects the timer D output
mode and input capture operation as shown in figure 64. It is reset to $0 by MCU reset.
• Timer write register D (TWDL: $011, TWDU: $012): Write-only register consisting of the lower digit
(TWDL) and the upper digit (TWDU). The operation of timer write register D is basically the same as
that of timer write register B (TWBL: $00A, TWBU: $00B).
• Timer read register D (TRDL: $011, TRDU: $012): Read-only register consisting of the lower digit
(TRDL) and the upper digit (TRDU). The operation of timer read register D is basically the same as
that of timer read register B (TRBL: $00A, TRBU: $00B).
When the input capture timer operation is selected and if the count of timer D is read after a trigger is
input, either the lower or upper digit can be read first.
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