Fujitsu 8FX User Manual

MB95630H Series
354 FUJITSU SEMICONDUCTOR LIMITED MN702-00009-2v0-E
CHAPTER 20 16-BIT RELOAD TIMER
20.1 Overview
20.1 Overview
The 16-bit reload timer has two counter operating modes in each of the two
clock modes.
The 16-bit reload timer can be used as an interval timer by generating an
interrupt when an underflow occurs in the timer.
■ Operation Modes of 16-bit Reload Timer
Table 20.1-1 shows the operation modes of the 16-bit reload timer.
■ Internal Clock Mode
Internal clock mode is selected when any value other than "0b111" is set to the count clock
setting bits (CSL[2:0]) in the 16-bit reload timer control status register (upper) ch. n
(TMCSRHn).
In internal clock mode, the following three trigger operation modes are available.
● Software trigger operation
With the count enable bit (CNTE) in the 16-bit reload timer control status register (lower) ch. n
(TMCSRLn) set to "1", the counter starts when the software trigger bit (TRG) in the
TMCSRLn register is set to "1".
● External trigger input operation
When the count enable bit (CNTE) in the 16-bit reload timer control status register (lower)
ch. n (TMCSRLn) is set to "1", the count will start if a valid edge (rising, falling, or both
selectable) specified by the operating mode select bits (MOD[2:0]) is input to the TIn pin.
● External gate input operation
When the count enable bit (CNTE) in the 16-bit reload timer control status register (lower)
ch. n (TMCSRLn) is set to "1", the count will start if a valid trigger input level ("L" or "H"
selectable) specified by the operating mode select bits (MOD[2:0]) is input to the TIn pin.
■ Event Count Mode (External Clock Mode)
When the count clock setting bits (CSL[2:0]) in the 16-bit reload timer control status register
(upper) ch. n (TMCSRHn) are set to "0b111", the count will start if a valid edge of trigger
input (rising, falling, or both) specified by the operating mode select bits (MOD[2:0]) is input
to the TIn pin. When an external clock is input in regular cycles, the reload timer can also be
used as an interval timer.
Table 20.1-1 Operation Modes of 16-bit Reload Timer
Clock mode Counter operating mode Trigger operation mode
Internal clock mode
Reload mode
Software trigger operation
External trigger input operation
External gate input operation
One-shot mode
Event count mode
(external clock mode)
Reload mode
Software trigger operation
One-shot mode

Fujitsu 8FX Specifications

General

Brand	Fujitsu
Model	8FX
Category	Computer Hardware
Language	English