GMS81C2020 Datasheet, PDF (54/92 Pages) Hynix Semiconductor – CMOS Single-Chip 8-Bit Microcontroller with A/D Converter & VFD Driver

GMS81C2020/GMS81C2120
Hyundai Micro Electro nics
15.2 16-bit Timer/Counter Mode
The Timer register is being run with 16 bits. A 16-bit timer/
counter register T0, T1 are increased from 0000_H until it
matches TDR0, TDR1 and then resets to 0000_H. The
match output generates Timer 0 interrupt not Timer 1 in-
terrupt.
The clock source of the Timer 0 is selected either internal
or external clock by bit T0CK2, T0CK1 and T0CK0.
In 16-bit mode, the bits T1CK1,T1CK0 and 16BIT of TM1
should be set to "1" respectively.
TM0
ADDRESS : D0H
-
-
CAP0 T0CK2 T0CK1 T0CK0 T0CN T0ST
RESET VALUE : --000000
-
-
0
X
X
X
X
X
TM1
POL
16BIT PWM1E CAP1 T1CK1 T1CK0 T1CN
T1ST
ADDRESS : D2H
RESET VALUE : 00000000
X
1
0
0
T0CK[2:0]
Edge Detector
T1CK[1:0]
T0CN
1
11
EC0
÷2
MUX
÷4
XX
÷8
fXI
÷ 32
÷ 128
÷ 512
÷1
fXI
÷2
÷8
÷ 2048
1
1
X
X
X : The value "0" or "1" corresponding your operation.
T0ST
0 : Stop
1 : Clear and Start
T1 ( 8-bit )
T0 ( 8-bit )
CLEAR
COMPARATOR
F/F
R40/T0O
R4FUNC.0
T0IF
TIMER 0
INTERRUPT
TDR1 ( 8-bit ) TDR0 ( 8-bit )
Figure 15-5 16-bit Timer / Counter Mode
15.3 8-bit Compare Output ( 16-bit )
The GMS81C2020 and GMS81C2120 has a function of
Timer Compare Output. To pulse out, the timer match can
goes to port pin(T0O, T1O) as shown in Figure 15-2 and
Figure 15-5 . Thus, pulse out is generated by the timer
match. These operation is implemented to pin, T0O,
PWM1O/T1O.
This pin output the signal having a 50 : 50 duty square
wave, and output frequency is same as below equation.


_
=
---------------
----^---^----^-^--^--^---^--^--^------- -------- ----^---^---- -------^---^----------------
 ×     × ( +  )
In this mode, the bit PWM1O/T1O of R5 function register
(R5FUNC.6) should be set to "1", and the bit PWM1E of
timer1 mode register ( TM1 ) should be set to "0".
In addition, 16-bit Compare output mode is available, also.
15.4 8-bit Capture Mode
The Timer 0 capture mode is set by bit CAP0 of timer
mode register TM0 (bit CAP1 of timer mode register TM1
for Timer 1) as shown in Figure 15-6 .
As mentioned above, not only Timer 0 but Timer 1 can also
be used as a capture mode.
The Timer/Counter register is increased in response inter-
nal or external input. This counting function is same with
normal timer mode, and Timer interrupt is generated when
54
preliminary
Nov. 1999 Ver 0.0