ez80l92 ZiLOG Semiconductor, ez80l92 Datasheet - Page 84

• Manufacturer Part Number: ez80l92
• Description: Ez80acclaim Flash Microcontrollers
• Manufacturer: ZiLOG Semiconductor

PS013014-0107
of the timer is achieved by loading
0000h
0000h
The time-out period of the PRT is returned by the following equation:
To calculate the time-out period with the above equation when using an initial value of
0000h
Minimum time-out duration is 4 times longer than the input clock period and is generated
by setting the clock divider ratio to 1:4 and the reload value to
duration is 2
setting the clock divider ratio to 1:256 and the reload value to
SINGLE PASS Mode
In SINGLE PASS mode, when the end-of-count value,
the timer is disabled, and the PRT_EN bit resets to 0. To restart the timer, the CPU must
reenable the timer by setting the PRT_EN bit to 1. An example of a PRT operating in
SINGLE PASS mode is illustrated in
in
PRT Time-Out Period
t
t
CNTH
CNTL
IOWRN
CLKEN
Table
CLK
IRQ
7:0]
7:0]
, because the timer first rolls over to
.
, enter a reload value of 65536 (
29.
24
(16,777,216) times longer than the input clock period and is generated by
Figure 19. PRT SINGLE PASS Mode Operation Example
0
=
4
Clock Divider Ratio x Reload Value
System Clock Frequency
0001h
3
Figure
FFFFh
. Maximum duration is achieved by loading
FFFFh
19. Timer register information is indicated
+ 1).
0
2
and then continues counting down to
0000h
1
0001h
0000h
, is reached, counting halts,
Programmable Reload Timers
Product Specification
. Maximum time-out
.
0
eZ80L92 MCU
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