HMS81016E HYNIX [Hynix Semiconductor], HMS81016E Datasheet - Page 35

• Manufacturer Part Number: HMS81016E
• Description: HYNIX SEMICONDUCTOR 8-BIT SINGLE-CHIP MICROCONTROLLERS
• Manufacturer: HYNIX [Hynix Semiconductor]

HMS81004E/08E/16E/24E/32E
pull-up is automatically disabled, if corresponding port is
selected as output.
9.3 R2 Port
R2 is an 8-bit CMOS bidirectional I/O port (address
0C4
an output through the R2DD register (address 0C5
R2 has internal pujll-ups that is independently connected
or disconnected by R2PC (address 0FA
isters for R2 are shown as below.
32
H
R2 Data Register (R/W)
R2
R2 Direction Register (W)
R2DD
R2 Pull-up Control Register (W)
R2PC
R2 Open drain Assign Register (W)
R2ODC
). Each I/O pin can independently used as an input or
-
-
-
R24 R23 R22 R21 R20
ADDRESS : 0C4
RESET VALUE : Undefined
ADDRESS : 0C5
RESET VALUE : 00
ADDRESS :0FA
RESET VALUE : 00
ADDRESS :0DF
RESET VALUE : 00
H
Port Direction
0: Input
1: Output
). The control reg-
Pull-up select
1: Without pull-up
0: With pull-up
Open drain select
0: Push-pull
1: Open drain
H
H
H
H
H
H
H
H
).
(1) R2 I/O Data Direction Register (R2DD)
R2 I/O Data Direction Register (R2DD) is 8-bit register,
and can assign input state or output state to each bit. If
R2DD is “1”, port R2 is in the output state, and if “0”, it is
in the input state. R2DD is write-only register. Since
R2DD is initialized as “00h” in reset state, the whole port
R2 becomes input state.
(2) R2 Data Register (R2)
R2 data register (R2) is 8-bit register to store data of port
R2. When set as the output state by R2DD, and data is writ-
ten in R2, data is outputted into R2 pin. When set as the in-
put state, input state of pin is read. The initial value of R2
is unknown in reset state.
(3) R2 Open drain Assign Register (R2ODC)
R2 Open Drain Assign Register (R2ODC) is 8bit register,
and can assign R2 port as open drain output port each bit,
if corresponding port is selected as output. If R2ODC is
selected as “1”, port R2 is open drain output, and if select-
ed as “0”, it is push-pull output. R2ODC is write-only reg-
ister and initialized as “00h” in reset state.
(4) R2 Pull-up Control Register (R2PC)
R2 Pull-up Control Register (R2PC) is 8-bit register and
can control pull-up on or off each bit, if corresponding port
is selected as input. If R2PC is selected as “1”, pull-up ia
disabled and if selected as ”0”, it is enabled. R2PC is write-
only register and initialized as “00h” in reset state. The
pull-up is automatically disabled, if corresponding port is
selected as output.
JUNE 2001 Ver 1.00