Z86D99 ZILOG [Zilog, Inc.], Z86D99 Datasheet - Page 42

• Manufacturer Part Number: Z86D99
• Description: Low-Voltage Micro controllers with ADC
• Manufacturer: ZILOG [Zilog, Inc.]

PS003807-1002
Clock
T
Logic
OSC
+2
IN
P3
1
Triggered Clock
Internal Clock
Gated Clock
External Clock
Internal
Clock
Counter/timer 1 is driven by a timer clock generated by dividing the internal clock
by four. The divide-by-four stage, the 6-bit prescaler, and the 8-bit counter/timer
form a synchronous 16-bit divide chain. Counter/timer T
external input (T
through which T
the end-of-count. Figure 18 is a block diagram of the counter/timer.
Figure 18. T
+4
1
Counter/Timer Block Diagram
1
IN
or the internal clock can be output. The timer output toggles at
) using Port P52. Port P5
P
R
E
Write
Down Counter
Initial Value
L
Register
PRE1
6-Bit
I
M
Z86D990/Z86D991 OTP and Z86L99X ROM
I
Low-Voltage Microcontrollers with ADC
N
6
can serve as a timer output (T
A
Write
Internal Data Bus
R
Down Counter
Initial Value
Register
Y
8-Bit
T1
1
can also be driven by an
Read
+2
Current Value
Register
T1
OUT
T
P5
IRQ5
OUT
6
)
35