st2032a Sitronix Technology Corporation, st2032a Datasheet - Page 14

• Manufacturer Part Number: st2032a
• Description: 8 Bit Microcontroller With 32k Bytes Rom
• Manufacturer: Sitronix Technology Corporation

10.2 Port-A
10.2.1 Port-A Description
Port-A is a bit-programmable bi-direction I/O port, which is
controlled by PCA register. It also provides bit programmable
pull-up resistor for each input pin. Two interrupts can be
10.2.2 Port-A I/O Control
Direction of Port-A is controlled by PCA. Each bit of PCA
controls the direction of one single I/O of Port-A respectively,
10.2.3 Port-A Pull-Up Option
Port-A contains PMOS transistors of pull-up resistor
controlled by software in bit-manner. In case of input
direction, on/off of the pull-up PMOS transistor is
controlled by the data wrote to data register, PA. “ 1” is
for enable and “ 0” is for disable. Above all, whole pull-up
control is by PULL bit of PMCR. Refer to FIGURE 10-1
for the block description.
Ver 2.4
Address Name
Address Name
Address Name
$03C
$000
$008
$00F
$03E
$008
$00F
Bit 7~0: PCA[7~0] : Port-A directional bits
Bit 7: PULL : Enable all pull-up function bit
Bit 6: PDBN : Enable Port-A interrupt de-bounce bit
Bit 5: INTEG : INTX interrupt edge select bit
PA
PCA
PMCR
IREQ
IENA
PCA
PMCR
1 = Enable pull-up function
0 = Disable pull-up function
1 = De-bounce for Port-A interrupt
0 = No de-bounce for Port-A interrupt
1 = Rising edge
0 = Falling edge
1 = Output mode
0 = Input mode
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
PCA[7]
PCA[7]
PULL
PULL
PA[7]
Bit 7
Bit 7
Bit 7
-
-
TABLE 10-4 Port Function Control Register (PMCR)
PCA[6]
PCA[6]
PDBN
PDBN
PA[6]
Bit 6
Bit 6
Bit 6
TABLE 10-3 Port-A Control Register (PCA)
TABLE 10-2 Summary Of Port-A Registers
-
-
PCA[5]
PCA[5]
INTEG
INTEG
PA[5]
IRBT
Bit 5
IEBT
Bit 5
Bit 5
PULL-UP
PCA[4]
PCA[4]
14/54
PORT
CONTROL
REGISTER
( PCR )
PORT
DATA
REGISTER
( PDR )
PA[4]
IRPT
IEPT
Bit 4
Bit 4
Bit 4
-
-
triggered by Port-A, de-bounced interrupt for keyboard-scan
and edge sensitive interrupt (PA0 only) for external event.
with “ 1” for output mode, and “ 0” for input mode.
PCA[3]
PCA[3]
PA[3]
Bit 3
IRT1
Bit 3
Bit 3
IET1
-
-
DATA INPUT
FIGURE 10-1 Port-A Block Diagram
PCA[2]
PCA[2]
PA[2]
Bit 2
Bit 2
Bit 2
IRT0
IET0
-
-
PCA[1]
PCA[1]
IRDAC
IEDAC
PA[1]
Bit 1
Bit 1
Bit 1
-
-
RD_INPUT
PCA[0]
PCA[0]
PA[0]
Bit 0
Bit 0
Bit 0
IRX
IEX
VCC
-
-
PULL-UP
100 -
- - 00 0000
- - 00 0000
0000 0000
0000 0000
PMOS
100 - - -00
1111 1111
Default
Default
Default
ST2032A
- - - -
9/13/07