NEC uPD78056Y User Manual

Page 259

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259

CHAPTER 12 CLOCK OUTPUT CONTROL CIRCUIT

Remarks 1. f

XX

: Main system clock frequency (f

X

or f

X

/2)

2. f

X

: Main system clock oscillation frequency

3. f

XT

: Subsystem clock oscillation frequency

4. TI00 : 16-bit timer/event counter input pin

5. TM0 : 16-bit timer register

6. MCS : Oscillation mode selection register (OSMS) bit 0

7. Figures in parentheses apply to operation with f

X

= 5.0 MHz or f

XT

= 32.768 kHz.

(2) Port mode register 3 (PM3)

This register set port 3 input/output in 1-bit units.

When using the P35/PCL pin for clock output function, set PM35 and output latch of P35 to 0.

PM3 is set with a 1-bit or 8-bit memory manipulation instruction.

RESET input sets PM3 to FFH.

Figure 12-4. Port Mode Register 3 Format

PM37

7

PM36

6

PM35 PM34

4

PM33

3

2

1

0

FF23H

Address

PM3

Symbol

PM32 PM31 PM30

5

FFH

After

Reset

R/W

R/W

PM3n

0

1

P3n Pin Input/Output Mode Selection (n = 0 to 7)

Output mode (output buffer ON)

Input mode (output buffer OFF)

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