ez80f92 ZiLOG Semiconductor, ez80f92 Datasheet - Page 83

• Manufacturer Part Number: ez80f92
• Description: Ez80acclaim Flash Microcontrollers
• Manufacturer: ZiLOG Semiconductor

Programmable Reload Timers
PS015313-0508
System Clock
RTC Source
GPIO Pin
Programmable Reload Timers Overview
(Timers 0—3
TMRx_IN
The eZ80F92 device features six Programmable Reload Timers (PRT). Each PRT contains
a 16-bit downcounter and a 16-bit reload register. In addition, each PRT features a clock
divider with four selectable taps for CLK ÷ 4, CLK ÷ 16, CLK ÷ 64, and CLK ÷ 256.
Each timer can be individually enabled to operate in either SINGLE PASS or CONTINU-
OUS mode. The timer can be programmed to start, stop, restart from the current value, or
restart from the initial value, and generate interrupts to the CPU.
Four of the Programmable Reload Timers (timers 0–3) feature a selectable clock source
input. The input for these timers can be either the system clock or the Real-Time Clock
(RTC) source. Timers 0–3 can also be used for event counting, with their inputs received
from a GPIO port pin. Output from timers 4 and 5 can be directed to a GPIO port pin.
Each of the six PRTs available on the eZ80F92 device can be controlled individually. They
do not share the same counters, reload registers, control registers, or interrupt signals.
A simplified block diagram of a programmable reload timer is displayed in
only)
2
Figure 20.Programmable Reload Timer Block Diagram
TMRx_CTL[3:2]
Adjustable
Prescaler
Clock
2
{TMRx_RR_H, TMRx_RR_L}
{TMRx_DR_H, TMRx_DR_L}
Reload Registers
Data Registers
Down Counter
Data[7:0]
Data[7:0]
16-Bit
Control Register
Control Logic
TMRx_CTL
Data[7:0]
PRT
(Timers 4—5 only)
Programmable Reload Timers
TOUT_EN
Product Specification
eZ80F92/eZ80F93
IRQ to eZ80 CPU
Timer Out
Figure
20.
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