M16C26A Datasheet, PDF (245/352 Pages) Renesas Technology Corp – 16-BIT SINGLE-CHIP MICROCOMPUTER M16C FAMILY / M16C/Tiny SERIES

M16C/26A Group (M16C/26A, M16C/26B, M16C/26T)
16. Programmable I/O Ports
f8
P85 / P17
Data Bus
Digital Debounce Filter
Clock
Port In
Signal Out
Reload Value
(write)
Count Value
(read)
To NMI and SD / INT5 and INPC17
Data Bus
f8
Reload Value
Port In
Signal Out
Count Value
FF
FF
1
03
03 02 01
2
3
03 02
4
01 00 FF
5
Reload Value
(continued)
Port In
(continued)
Signal Out
(continued)
Count Value
(continued)
03
FF
FF
03 02 01 00
FF
6
7
03 02 FF
8
9
1. (Condition after reset). Reload = FF, Port In = signal Out continuosly.
2. Reload = 03. At edge of Port In != Signal Out, Counter gets Reload Value and
stats counting down.
3. Port In = Signal Out, counting stops.
4. At edge of Port In != Signal Out, Counter gets Reload Value and starts counting.
5. Counter underflows, stops, and Port In is driven to Signal Out.
6. At edge of Port In != Signal Out, counter gets Reload Value and starts counting.
7. Counter underflows, stops, and Port In is driven to Signal Out.
8. At edge of Port In != Signal Out, counter gets Reload Value and starts counting.
9. FF is written to Reload Value. Counter is stopped and loaded with FF.
Port In = Signal Out continuously.
Figure 16.6.2. Functioning of Digital Debounce Filter
Rev. 2.00 Feb.15, 2007 ^{page 228} of 329
REJ09B0202-0200