NEC uPD78056Y User Manual

Page 190

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190

CHAPTER 8 16-BIT TIMER/EVENT COUNTER

0

0

0

0

0

0

SCS1 SCS0

7

6

5

4

3

2

1

0

Symbol

SCS

FF47H

00H

R/W

Address

After Reset

R/W

SCS1 SCS0

0

0

0

1

1

0

1

1

INTP0 Sampling Clock Selection

MCS = 1

MCS = 0

f

XX

/2

N

f

X

/2

7

(39.1 kHz)

f

XX

/2

7

f

X

/2

8

(19.5 kHz)

f

X

/2

5

(156.3 kHz)

f

XX

/2

5

f

X

/2

6

(78.1 kHz)

f

X

/2

6

(78.1 kHz)

f

XX

/2

6

f

X

/2

7

(39.1 kHz)

(7) Sampling clock select registers (SCS)

This register sets clocks which undergo clock sampling of valid edges to be input to INTP0. When remote

controlled reception is carried out using INTP0, digital noise is removed with sampling clock.

SCS is set with an 8-bit memory manipulation instruction.

RESET input sets SCS value to 00H.

Figure 8-9. Sampling Clock Select Register Format

Caution f

XX

/2

N

is the clock supplied to the CPU, and f

XX

/2

5

, f

XX

/2

6

, and f

XX

/2

7

are clocks supplied to

peripheral hardware. f

XX

/2

N

is stopped in HALT mode.

Remarks

1. N

: Value set in bits 0 to 2 (PCC0 to PCC2) of the processor clock control register (PCC)

(N = 0 to 4)

2. f

XX

: Main system clock frequency (f

X

or f

X

/2)

3. f

X

: Main system clock oscillation frequency

4. MCS

: Bit 0 of oscillation mode selection register (OSMS)

5. Figures in parentheses apply to operation with f

X

= 5.0 MHz.

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