10 I/O PORTS (P)
S1C17704 TECHNICAL MANUAL
EPSON
10-19
0x5208: P0 Port Chattering Filter Control Register (P0_CHAT)
Register name Address
Bit
Name
Function
Setting
Init. R/W
Remarks
P0 Port
Chattering
Filter Control
Register
(P0_CHAT)
0x5208
(8 bits)
D7
–
reserved
–
–
–
0 when being read.
D6–4
P0CF2[2:0]
P0[7:4] chattering filter time
P0CF2[2:0]
Filter time
0
R/W
0x7
0x6
0x5
0x4
0x3
0x2
0x1
0x0
16384/f
PCLK
8192/f
PCLK
4096/f
PCLK
2048/f
PCLK
1024/f
PCLK
512/f
PCLK
256/f
PCLK
None
0x0
R/W
D3
–
reserved
–
–
–
0 when being read.
D2–0
P0CF1[2:0]
P0[3:0] chattering filter time
P0CF1[2:0]
Filter time
0x0
R/W
0x7
0x6
0x5
0x4
0x3
0x2
0x1
0x0
16384/f
PCLK
8192/f
PCLK
4096/f
PCLK
2048/f
PCLK
1024/f
PCLK
512/f
PCLK
256/f
PCLK
None
D7 Reserved
D[6:4]
P0CF2[2:0]: P0[7:4] Chattering Filter Time Select Bits
Configures the chattering filter for the P0[7:4] ports.
D3 Reserved
D[2:0]
P0CF1[2:0]: P0[3:0] Chattering Filter Time Select Bits
Configures the chattering filter for the P0[3:0] ports.
The P0 ports are equipped with a chattering filter. Use P0CF
x
[2:0] to select whether the filter for
P0[3:0] or P0[7:4] is used or not and also select an input level check time when the filter is used.
Table 10.8.2 Setting Input Level Check Time
P0CF
x
[2:0]
Check time
*
0x7
16384/f
PCLK
(8 ms)
0x6
8192/f
PCLK
(4 ms)
0x5
4096/f
PCLK
(2 ms)
0x4
2048/f
PCLK
(1 ms)
0x3
1024/f
PCLK
(512 µs)
0x2
512/f
PCLK
(256 µs)
0x1
256/f
PCLK
(128 µs)
0x0
Disabled (Off)
(Default: 0x0,
∗
when OSC3 = 2 MHz, PCLK = OSC3)
Notes
: • The check time to eliminate chattering means the maximum pulse width that can be
eliminated. The valid interrupt input needs a pulse width of the set check time (minimum) to
twice that of the check time (maximum).
• Input interrupts cannot be accepted in SLEEP mode if the CPU enters SLEEP mode when
the chattering filter is active. The chattering filter should be disabled (off) before executing
the
slp
instruction.
• Be sure to disable the P0 port interrupt before changing the P0_CHAT register. Unnecessary
interrupt may occur if the register is changed when the P0 port interrupt has been enabled.
• The internal signal may oscillate if the rise/fall time of the input signal is too long because
the input signal level transition to the threshold level duration of time is too long. This causes
the input interrupt to malfunction, therefore setup the input signal so that the rise/fall time is
25 ns or less.
Summary of Contents for S1C17704
Page 1: ...TECHNICAL MANUAL S1C17704 CMOS 16 BIT SINGLE CHIP MICROCOMPUTER ...
Page 22: ...1 OVERVIEW 1 10 EPSON S1C17704 TECHNICAL MANUAL THIS PAGE IS BLANK ...
Page 42: ...3 MEMORY MAP BUS CONTROL 3 12 EPSON S1C17704 TECHNICAL MANUAL THIS PAGE IS BLANK ...
Page 82: ...6 INTERRUPT CONTROLLER ITC 6 26 EPSON S1C17704 TECHNICAL MANUAL THIS PAGE IS BLANK ...
Page 108: ...8 CLOCK GENERATOR CLG 8 8 EPSON S1C17704 TECHNICAL MANUAL THIS PAGE IS BLANK ...
Page 112: ...9 PRESCALER PSC 9 4 EPSON S1C17704 TECHNICAL MANUAL THIS PAGE IS BLANK ...
Page 138: ...10 I O PORTS P 10 26 EPSON S1C17704 TECHNICAL MANUAL THIS PAGE IS BLANK ...
Page 156: ...11 16 BIT TIMERS T16 11 18 EPSON S1C17704 TECHNICAL MANUAL THIS PAGE IS BLANK ...
Page 208: ...14 8 BIT OSC1 TIMER T8OSC1 14 16 EPSON S1C17704 TECHNICAL MANUAL THIS PAGE IS BLANK ...
Page 234: ...16 STOPWATCH TIMER SWT 16 14 EPSON S1C17704 TECHNICAL MANUAL THIS PAGE IS BLANK ...
Page 242: ...17 WATCHDOG TIMER WDT 17 8 EPSON S1C17704 TECHNICAL MANUAL THIS PAGE IS BLANK ...
Page 264: ...18 UART 18 22 EPSON S1C17704 TECHNICAL MANUAL THIS PAGE IS BLANK ...
Page 300: ...20 I2C 20 20 EPSON S1C17704 TECHNICAL MANUAL THIS PAGE IS BLANK ...
Page 320: ...21 REMOTE CONTROLLER REMC 21 20 EPSON S1C17704 TECHNICAL MANUAL THIS PAGE IS BLANK ...
Page 360: ...24 ON CHIP DEBUGGER DBG 24 6 EPSON S1C17704 TECHNICAL MANUAL THIS PAGE IS BLANK ...
Page 362: ...25 BASIC EXTERNAL WIRING DIAGRAM 25 2 EPSON S1C17704 TECHNICAL MANUAL THIS PAGE IS BLANK ...