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Rev. 1.40
96
March 29, 2019
Rev. 1.40
97
March 29, 2019
HT45F23A/HT45F24A
TinyPower
TM
Flash MCU with OPA & Comparators
HT45F23A/HT45F24A
TinyPower
TM
Flash MCU with OPA & Comparators
Register
Name
Bit
7
6
5
4
3
2
1
0
SIMC0
SIM2
SIM1
SIM0
PCKEN
PCKP1
PCKP0
SIMEN
—
SIMC1
HCF
HAAS
HBB
HTX
TXAK
SRW
IAMWU
RXAK
SIMD
D7
D6
D5
D4
D3
D2
D1
D0
SIMA
IICA6
IICA5
IICA4
IICA3
IICA2
IICA1
IICA0
—
I
2
C Registers List
SIMC0 Register
Bit
7
6
5
4
3
2
1
0
Name
SIM2
SIM1
SIM0
PCKEN
PCKP1
PCKP0
SIMEN
—
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
—
POR
1
1
1
0
0
0
0
—
Bit 7~5
SIM2, SIM1, SIM0
: Operating Mode Control
000: SPI master mode; SPI clock is f
SYS
/4
001: SPI master mode; SPI clock is f
SYS
/16
010: SPI master mode; SPI clock is f
SYS
/64
011: SPI master mode; SPI clock is f
SUB
100: SPI master mode; SPI clock is Timer 0 output/2 (PFD0)
101: SPI slave mode
110: I
2
C slave mode
111: Unused mode
These bits setup the overall operating mode of the SIM function. As well as selecting
if the I
2
C or SPI function, they are used to control the SPI Master/Slave selection and
the SPI Master clock frequency. The SPI clock is a function of the system clock but
can also be chosen to be sourced from the Timer 0. If the SPI Slave Mode is selected
then the clock will be supplied by an external Master device.
Bit 4
PCKEN
: PCK Output Pin Control
0: Disable
1: Enable
Bit 3~2
PCKP1, PCKP0
: Select PCK output pin frequency
00: f
SYS
01: f
SYS
/4
10: f
SYS
/8
11: Timer 0 output/2 (PFD0)
Bit 1
SIMEN
: SIM Control
0: Disable
1: Enable
The bit is the overall on/off control for the SIM interface. When the SIMEN bit is
cleared to zero to disable the SIM interface, the SDI, SDO, SCK and SCS, or SDA
and SCL lines will be in a
floating condition and the SIM operating current will be
reduced to a minimum value. When the bit is high the SIM interface is enabled. The
SIM configuration option must have first enabled the
SIM interface for this bit to be
effective. If the SIM is configured to operate as an SPI interface via
SIM2~SIM0 bits,
the contents of the SPI control registers will remain at the previous settings when the
SIMEN bit changes from low to high and should therefore be first initialised by the
application program. If the SIM is configured to operate as an I
2
C interface via the
SIM2~SIM0 bits and the SIMEN bit changes from low to high, the contents of the I
2
C
control bits such as HTX and TXAK will remain at the previous settings and should
therefore be first initialised by the application program while the relevant I
2
C flags
such as HCF, HAAS, HBB, SRW and RXAK will be set to their default states.
Bit 0
unimplemented, read as “0”