st2024c Sitronix Technology Corporation, st2024c Datasheet - Page 14

• Manufacturer Part Number: st2024c
• Description: 24k 8-bit Single Chip Microcontroller
• Manufacturer: Sitronix Technology Corporation

10.2.3 PORT-A PULL-UP OPTION
PORT-A contains pull-up MOS transistors controlled by
software. When an I/O is used as an input. The ON/OFF of
the pull-up MOS transistor will be controlled by port data
register (PA) and the pull-up MOS will be enabled with “1”
Ver 2.2
Address Name
$00F
Bit 7:
Bit 6:
Bit 5:
PMCR
PULL : Enable all pull-up function bit
PDBN : Enable Port-A interrupt debounce bit
INTEG : INTX interrupt edge select bit
1 = Enable pull-up function
0 = Disable pull-up function
1 = Debounce for Port-A interrupt
0 = No debounce for Port-A interrupt
1 = Rising edge
0 = Falling edge
R/W
R/W
TABLE 10-9: PORT CONDITION CONTROL REGISTER (PMCR)
FIGURE 10-1: Port-A Configuration Function Block Diagram
PULL-UP
PORT
CONTROL
REGISTER
( PCR )
PORT
DATA
REGISTER
( PDR )
PULL
Bit 7
PDBN
Bit 6
DATA INPUT
INTEG
Bit 5
14/54
Bit 4
for data bit and disable with “0” for data bit. The PULL
control bit of PMCR controls the ON/OFF of all the pull-up
MOS simultaneously. Please refer to the Figure 9-1.
-
RD_INPUT
Bit 3
VCC
-
PULL-UP
PMOS
Bit 2
-
PSG0
Bit 1
PSGB
Bit 0
100 - - -00
ST2024C
Default
1/31/08