Z86D99 ZILOG [Zilog, Inc.], Z86D99 Datasheet - Page 80

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

PS003807-1002
_____2__
______10
Bit
Bit/Field
R/W
Reset
R = Read, W = Write, X = Indeterminate
Bit
Position
765432__
_______1_
________0
Table 35. TMR Register [Group/Bank F0h, Register 1 (R241)] (Continued)
T1 Prescale Register (PRE1)
The T1 prescaler consists of an 8-bit register and a 6-bit down-counter. The six
most significant bits (D2–D7) of PRE1 hold the prescaler’s count modulo, a value
from 1 to 64 decimal, as shown in Table 36. The prescale register also contains
control bits that specify the counting mode and clock source for T1.
Table 36. PRE1 Register [Group/Bank F0h, Register 3 (R243)]
Timer Control Registers—T8 and T16 Timers
One of the unique features of the Z86D99/Z86L99 family is a special timer archi-
tecture to automate the generation and reception of complex pulses or signals.
This timer architecture consists of one programmable 8-bit counter timer with two
capture registers and two load registers and a programmable 16-bit counter/timer
with one 16-bit capture register pair and one 16-bit load register pair and their
associated control registers. These counter/timers can work independently or can
be combined together using a number of user-selectable modes governed by the
T8/T16 control registers.
T
Reserved
7
Prescaler_Modulo
R/W
0
Bit/Field
Prescaler Modulo R/W
Clock Source
Count Mode
1
Load
P
6
R/W
0
R
E
L
R/W
R
W
5
R/W
0
R/W
R/W
R/W
I
M
Z86D990/Z86D991 OTP and Z86L99X ROM
1
0
1
X
4
R/W
0
Value
Data
1
0
1
0
I
Low-Voltage Microcontrollers with ADC
N
A
Load T
No effect
Always reads 11
No effect
3
R/W
0
Description
Range: 1 to 64 Decimal
T
T
T
T
1
1
1
1
R
Internal
External (T
Modulo-n
Single Pass
Y
1
2
R/W
0
IN
on P52)
1
Clock_
Source
R/W
0
0
Count_
Mode
R/W
0
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