HD404344R Datasheet, PDF (55/102 Pages) Renesas Technology Corp – 4-bit microcomputer has an A/D converter

HD404344R Series/HD404394 Series
• Timer mode register B2 (TMB2: $026): Two-bit write-only register that sets the input edge detection of
pin EVNB, as shown in figure 28. It is reset to $0 by an MCU reset.
Timer mode register B2 (TMB2: $026)
Bit
Initial value
Read/Write
Bit name
3
2
1
—
—
0
—
—
W
Not used Not used TMB21
0
0
W
TMB20
TMB21 TMB20
0
0
1
1
0
1
EVNB Edge Detection Selection
No detection
Falling-edge detection
Rising-edge detection
Rising- and falling-edge detection
Figure 28 Timer Mode Register B2 (TMB2)
• Timer write register B (TWBL: $00A, TWBU: $00B): Write-only register consisting of the lower digit
(TWBL) and the upper digit (TWBU). The lower digit is reset to $0 by MCU reset, but the upper digit
value cannot be guaranteed. See figures 29 and 30.
Timer B is initialized by writing to timer write register B (TWBL: $00A, TWBU: $00B). In this case,
the lower digit (TWBL) must be written to first, but writing only to the lower digit does not change the
timer B value. Timer B is initialized to the value in timer write register B at the same time the upper
digit (TWBU) is written to. When timer write register B is written to again and if the lower digit value
needs no change, writing only to the upper digit initializes timer B.
Timer write register B (lower) (TWBL: $00A)
Bit
Initial value
Read/Write
Bit name
3
0
W
TWBL3
2
0
W
TWBL2
1
0
W
TWBL1
0
0
W
TWBL0
Figure 29 Timer Write Register B (lower) (TWBL)
Timer write register B (upper) (TWBU: $00B)
Bit
Initial value
Read/Write
Bit name
3
2
1
0
Undefined Undefined Undefined Undefined
W
W
W
W
TWBU3 TWBU2 TWBU1 TWBU0
Figure 30 Timer Write Register B (upper) (TWBU)
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