HD404669 Datasheet, PDF (76/142 Pages) Hitachi Semiconductor – Low-Voltage AS Microcomputers with On-Chip DTMF Generation Circuit

HD404669 Series
Detection edge select register 2 (ESR2: $027): Write-only register that selects the detection edge of
signals input to pin EVND as shown in figure 57. It is reset to $0 by an MCU reset or in stop mode.
Detection edge select register 2 (ESR2: $027)
Bit
Initial value
Read/Write
Bit name
3
0
W
ESR23
2
0
W
ESR22
1
0
W
ESR21
0
0
W
ESR20
ESR23 ESR22
0
0
1
1
0
1
EVND detection edge
No detection
Falling-edge detection
Rising-edge detection
Double-edge detection^*
ESR21 ESR20
0
0
1
1
0
1
INT₄ detection edge
No detection
Falling-edge detection
Rising-edge detection
Double-edge detection^*
Note: * Both falling and rising edges are detected.
Figure 57 Detection Edge Select Register 2 (ESR2)
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