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Rev. 1.21
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Rev. 1.21
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HT66F488/HT66F489
A/D Flash MCU with EEPROM
HT66F488/HT66F489
A/D Flash MCU with EEPROM
Pin Name
Function
OPT
I/T
O/T
Description
PB3/OSC2/XT2/
SSEG15
PB3
PBPU
ST
CMOS Gene�al pu�pose I/O. Registe� ena�le pull-up.
OSC2
CO
—
HXT HXT pin
XT2
CO
—
LXT LXT pin
SSEG15 SLCDC3
—
CMOS Softwa�e LCD SEG output
PB4/OSC1/
XT1/ICPCK/
SSEG14
PB4
PBPU
ST
CMOS Gene�al pu�pose I/O. Registe� ena�le pull-up.
OSC1
CO
HXT
—
HXT pin
XT1
CO
LXT
—
LXT pin
ICPCK
—
ST
—
ICP Clock pin
SSEG14 SLCDC3
—
CMOS Softwa�e LCD SEG output
PB5/SSEG2�
PB5
PBPU
ST
CMOS Gene�al pu�pose I/O. Registe� ena�le pull-up.
SSEG2� SLCDC4
—
CMOS Softwa�e LCD SEG output
PB6/STCK/TX/
A��/SSEG28
PB6
PBPU
ST
CMOS Gene�al pu�pose I/O. Registe� ena�le pull-up.
STCK
—
ST
—
STM input
TX
—
—
CMOS UART data t�ans�ission output
A��
ACERL
A�
—
ADC input
SSEG28 SLCDC4
—
CMOS Softwa�e LCD SEG output
PB�/STP/RX/
A�1/SSEG2�
PB�
PBPU
ST
CMOS Gene�al pu�pose I/O. Registe� ena�le pull-up.
STP
TMPC�
ST
CMOS STM input/output
RX
—
ST
—
UART data �eceived input
A�1
ACERL
A�
—
ADC input
SSEG2� SLCDC4
—
CMOS Softwa�e LCD SEG output
PC�/A�2/
SSEG26
PC�
PCPU
ST
CMOS Gene�al pu�pose I/O. Registe� ena�le pull-up.
A�2
ACERL
A�
—
ADC input
SSEG26 SLCDC4
—
CMOS Softwa�e LCD SEG output
PC1/SSEG25
PC1
PCPU
ST
CMOS Gene�al pu�pose I/O. Registe� ena�le pull-up.
SSEG25 SLCDC4
—
CMOS Softwa�e LCD SEG output
PC2/SSEG24
PC2
PCPU
ST
CMOS Gene�al pu�pose I/O. Registe� ena�le pull-up.
SSEG24 SLCDC4
—
CMOS Softwa�e LCD SEG output
PC3/A�3/
SSEG23
PC3
PCPU
ST
CMOS Gene�al pu�pose I/O. Registe� ena�le pull-up.
A�3
ACERL
A�
—
ADC input
SSEG23 SLCDC4
—
CMOS Softwa�e LCD SEG output
PC4/A�4/
SSEG22
PC4
PCPU
ST
CMOS Gene�al pu�pose I/O. Registe� ena�le pull-up.
A�4
ACERL
A�
—
ADC input
SSEG22 SLCDC4
—
CMOS Softwa�e LCD SEG output
PC5/A�5/I�T3/
SSEG21
PC5
PCPU
ST
CMOS Gene�al pu�pose I/O. Registe� ena�le pull-up.
A�5
ACERL
A�
—
ADC input
I�T3
—
ST
—
Exte�nal inte��upt input
SSEG21 SLCDC3
—
CMOS Softwa�e LCD SEG output
PC6/A�6/VREF/
I�T2/SSEG2�
PC6
PCPU
ST
CMOS Gene�al pu�pose I/O. Registe� ena�le pull-up.
A�6
ACERL
A�
—
ADC input
VREF
ADCR1
A�
—
ADC Refe�ence voltage input
I�T2
—
ST
—
Exte�nal inte��upt input
SSEG2� SLCDC3
—
CMOS Softwa�e LCD SEG output
PC�/I�T5/
SSEG1�
PC�
PCPU
ST
CMOS Gene�al pu�pose I/O. Registe� ena�le pull-up.
I�T5
—
ST
—
Exte�nal inte��upt input
SSEG1� SLCDC3
—
CMOS Softwa�e LCD SEG output