GMS77C1001 Datasheet, PDF (28/44 Pages) Hynix Semiconductor – 8-BIT SINGLE-CHIP MICROCONTROLLERS

GMS77C1000/GMS77C1001
11. TIMER0 MODULE AND TMR0 REGISTER
The Timer0 module has the following features:
• 8-bit timer/counter register, TMR0
• 8-bit software programmable prescaler
• Internal or external clock select
• Edge select for external clock
Figure 11-1 is a simplified block diagram of the Timer0
module, while Figure 11-2 shows the electrical structure of
the Timer0 input.
T_CY ( = F_OSC/4)
EC0
pin
T0SE
0
MUX
1
T0CS
1
MUX
0
PSA
Sync with
Internal
Clocks
(2cycle delay)
Watchdog
Timer
WDT Enable bit
0
MUX
1
PSA
clear
8-bit Prescaler
8
8 - to - 1 MUX
PS2:PS0
0
1
MUX
PSA
Data bus
8
TMR0 reg
WDT Time-Out
FIGURE 11-1 BLOCK DIAGRAM OF THE TIMER0/WDT PRESCALER
ECO
pin
P
R_IN
(1)
N
Noise Filter
Schmitt Trigger
Input Buffer
Note 1: ESD protection circuits
FIGURE 11-2 ELECTRICAL STRUCTURE OF EC0 PIN
July. 2001 Ver. 1.1
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