Renesas 4513 Manual De Usuario

4513/4514 Group User’s Manual

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The 4513/4514 Group has the programmable timers.

• Programmable timer

The programmable timer has a reload register and enables the

frequency dividing ratio to be set. It is decremented from a setting

value n. When it underflows (count to n + 1), a timer interrupt re-

quest flag is set to “1,” new data is loaded from the reload

register, and count continues (auto-reload function).

• Fixed dividing frequency timer

The fixed dividing frequency timer has the fixed frequency divid-

ing ratio (n). An interrupt request flag is set to “1” after every n

count of a count pulse.

FF

16

n

00

16

n : Counter initial value

Count starts

Reload

Reload

1st underflow

2nd underflow

n+1 count

n+1 count

Time

An interrupt occurs or 

a skip instruction is executed.

Timer  interrupt 
request flag

The contents of counter

“1”

“0”