HT66F25D View Datasheet(PDF) - Holtek Semiconductor
Part Name
Description
MFG CO.
'HT66F25D' PDF : 177 Pages View PDF
A/D Flash Type 8-bit MCU with EEPROM
HT66F24D/HT66F25D
Input/Output Ports
Holtek microcontrollers offer considerable flexibility on their I/O ports. With the input or output
designation of every pin fully under user program control, pull-high selections for all ports and
wake-up selections on certain pins, the user is provided with an I/O structure to meet the needs of a
wide range of application possibilities.
The device provides bidirectional input/output lines labeled with port names PA~PD. These I/O
ports are mapped to the RAM Data Memory with specific addresses as shown in the Special Purpose
Data Memory table. All of these I/O ports can be used for input and output operations. For input
operation, these ports are non-latching, which means the inputs must be ready at the T2 rising edge
of instruction “MOV A,[m]”, where m denotes the port address. For output operation, all the data is
latched and remains unchanged until the output latch is rewritten.
I/O Resistor Lists
HT66F24D
Register
Name
PAWU
PAPU
PAC
PA
PBPU
PB
PBC
PCPU
PC
PCC
7
PAWU7
PAPU7
PAC7
PA7
—
—
—
PCPU7
PCC7
PC7
6
PAWU6
PAPU6
PAC6
PA6
—
—
—
PCPU6
PCC6
PC4
5
PAWU5
PAPU5
PAC5
PA5
PBPU5
PBC5
PB5
PCPU5
PCC5
PC5
Bit
4
3
PAWU4 PAWU3
PAPU4 PAPU3
PAC4
PAC3
PA4
PA3
PBPU4 PBPU3
PBC4
PBC3
PB4
PB3
PCPU4 PCPU3
PCC4
PCC3
PC4
PC3
2
PAWU2
PAPU2
PAC2
PA2
PBPU2
PBC2
PB2
PCPU2
PCC2
PC2
1
PAWU1
PAPU1
PAC1
PA1
PBPU1
PBC1
PB1
PCPU1
PCC1
PC1
0
PAWU0
PAPU0
PAC0
PA0
PBPU0
PBC0
PB0
PCPU0
PCC0
PC0
HT66F25D
Register
Name
PAWU
PAPU
PAC
PA
PBPU
PB
PBC
PCPU
PC
PCC
PDPU
PD
PDC
7
PAWU7
PAPU7
PAC7
PA7
PBPU7
PBC7
PB7
PCPU7
PCC7
PC7
—
—
—
6
PAWU6
PAPU6
PAC6
PA6
PBPU6
PBC6
PB6
PCPU6
PCC6
PC4
—
—
—
5
PAWU5
PAPU5
PAC5
PA5
PBPU5
PBC5
PB5
PCPU5
PCC5
PC5
—
—
—
Bit
4
3
PAWU4 PAWU3
PAPU4 PAPU3
PAC4
PAC3
PA4
PA3
PBPU4 PBPU3
PBC4
PBC3
PB4
PB3
PCPU4 PCPU3
PCC4
PCC3
PC4
PC3
—
—
—
—
—
—
2
PAWU2
PAPU2
PAC2
PA2
PBPU2
PBC2
PB2
PCPU2
PCC2
PC2
—
—
—
1
PAWU1
PAPU1
PAC1
PA1
PBPU1
PBC1
PB1
PCPU1
PCC1
PC1
PDPU1
PDC1
PD1
0
PAWU0
PAPU0
PAC0
PA0
PBPU0
PBC0
PB0
PCPU0
PCC0
PC0
PDPU0
PDC0
PD0
Rev. 1.10
60
March 25, 2013
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