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NEC switch User Manual

Page 81

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CHAPTER 6 8-BIT TIMER/EVENT COUNTERS 00 AND 01

User’s Manual U12978EJ3V0UD

81

Figure 6-2. Block Diagram of 8-Bit Timer/Event Counter 01

Internal bus

8-bit compare register 01

(CR01)

Match

TO01/P26/
INTP0/TI01

INTTM01

f

X

/2

4

f

X

/2

8

TI01/P26

/INTP0/TO01

Selector

Clear

8-bit timer counter 01

(TM01)

2

Internal bus

TCE01 TCL011 TCL010 TOE01

8-bit timer mode control register 01 (TMC01)

F/F

P26

Output latch

PM26

Selector

(1) 8-bit compare register 0n (CR0n)

This is an 8-bit register used to compare the value set to CR0n with the 8-bit timer counter 0n (TM0n) count

value, and if they match, generate used an interrupt request (INTTM0n).

CR0n is set with an 8-bit memory manipulation instruction. Values from 00H to FFH can be set.

RESET input sets CR0n undefined.

Caution

Be sure to set CR0n after the timer operation is stopped.

Remark

n = 0 or 1

(2) 8-bit timer counter 0n (TM0n)

This is an 8-bit register used to count pulses.

TM0n is read with an 8-bit memory manipulation instruction.

RESET input sets TMn to 00H.

Remark

n = 0 or 1