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Rev. 2.50
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Rev. 2.50
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HT66F20/HT66F30/HT66F40/HT66F50/HT66F60
HT66FU30/HT66FU40/HT66FU50/HT66FU60
A/D Flash MCU with EEPROM
HT66F20/HT66F30/HT66F40/HT66F50/HT66F60
HT66FU30/HT66FU40/HT66FU50/HT66FU60
A/D Flash MCU with EEPROM
S T A R T s i g n a l
f r o m M a s t e r
S e n d s l a v e a d d r e s s
a n d R / W b i t f r o m M a s t e r
A c k n o w l e d g e
f r o m s l a v e
S e n d d a t a b y t e
f r o m M a s t e r
A c k n o w l e d g e
f r o m s l a v e
S T O P s i g n a l
f r o m M a s t e r
I
2
C Registers
There are three control registers associated with the I
2
C bus, SIMC0, SIMC1 and SIMA and one
data register, SIMD. The SIMD register, which is shown in the above SPI section, is used to store
the data being transmitted and received on the I
2
C bus. Before the microcontroller writes data to
the I
2
C bus, the actual data to be transmitted must be placed in the SIMD register. After the data is
received from the I
2
C bus, the microcontroller can read it from the SIMD register. Any transmission
or reception of data from the I
2
C bus must be made via the SIMD register.
Note that the SIMA register also has the name SIMC2 which is used by the SPI function. Bit SIMEN
and bits SIM2~SIM0 in register SIMC0 are used by the I
2
C interface.
Register
Name
Bit
7
6
5
4
3
2
1
0
SIMC0
SIM2
SIM�
SIM0
PCKEN
PCKP�
PCKP0
SIMEN
—
SIMC�
HCF
HAAS
HBB
HTX
TXAK
SRW
IAMWU
RXAK
SIMD
D�
D6
D5
D4
D3
D2
D�
D0
SIMA
IICA6
IICA5
IICA4
IICA3
IICA2
IICA�
IICA0
D0
I
2
C Registers List