6 precautions when using 16-bit reload timer, Precautions when using 16-bit reload timer – FUJITSU F2MCTM-16LX User Manual

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CHAPTER 14 16-BIT RELOAD TIMER

14.6

Precautions when Using 16-bit Reload Timer

This section explains the precautions when using the 16-bit reload timer.

■

Precautions when Using 16-bit Reload Timer

●

Precautions when setting by program

•

Set the 16-bit reload register (TMRLR) after disabling the timer operation (TMCSR:CNTE = 0)

•

The 16-bit timer register (TMR) can be read during the TMR count operation. However, always use the

word instruction.

•

Change the CSL1 and CSL0 bits in the TMCSR after disabling the timer operation (TMCSR:CNTE = 0)

●

Precautions on interrupt

•

When the UF bit in the TMCSR is set to 1 and the underflow interrupt output is enabled (TMCSR:INTE

= 1), it is impossible to return from interrupt processing. Always clear the UF bit. However, when the

EI

2

OS is used, the UF bit is cleared automatically.

•

When using the EI

2

OS in the 16-bit reload timer, it is necessary to disable the interrupt of the 16-bit

reload timer that shares the interrupt control register (ICR).

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