HT83003 HOLTEK [Holtek Semiconductor Inc], HT83003 Datasheet - Page 17

• Manufacturer Part Number: HT83003
• Description: Q-Voice
• Manufacturer: HOLTEK [Holtek Semiconductor Inc]

Input/Output Ports
There are 8 bidirectional input/output lines in the
microcontroller, labeled from PA, which are mapped to
the data memory of [12H] respectively. All of these I/O
ports can be used for input and output operations. For
input operation, these ports are non-latching, that is, the
inputs must be ready at the T2 rising edge of instruction
data is latched and remains unchanged until the output
latch is rewritten.
Each I/O line has its own control register (PAC) to con-
trol the input/output configuration. With this control reg-
ister, CMOS output or Schmitt trigger input with or
without pull-high resistor structures can be reconfigured
dynamically under software control. To function as an in-
put, the corresponding latch of the control register must
write 1 . The input source also depends on the control
register. If the control register bit is 1 , the input will
read the pad state. If the control register bit is 0 , the
contents of the latches will move to the internal bus. The
latter is possible in the read-modify-write instruction.
Rev. 0.10
MOV A, [m] (m=12H). For output operation, all the
Input/Output Ports
Preliminary
17
For output function, CMOS is the only configuration.
These control registers are mapped to locations 13H.
After a chip reset, these input/output lines remain at high
levels or floating state (dependent on pull-high options).
Each bit of these input/output latches can be set or
cleared by SET [m].i and CLR [m].i (m=12H) instruc-
tions.
Some instructions first input data and then follow the
output operations. For example, SET [m].i , CLR
[m].i , CPL [m] , CPLA [m] read the entire port states
into the CPU, execute the defined operations
(bit-operation), and then write the results back to the
latches or the accumulator.
Each line of port A has the capability of waking-up the
device. The wake-up capability of port A is determined
by mask option. There is a pull-high option available for
all I/O lines. Once the pull-high option is selected, all I/O
lines have pull-high resistors. Otherwise, the pull-high
resistors are absent. It should be noted that a
non-pull-high I/O line operating in input mode will cause
a floating state.
August 25, 2003
HT83XXX