Holtek BS83A04C, Руководство пользователя

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Rev. 1.00 88 March 24, 2020 Rev. 1.00 89 March 24, 2020
BS83A04C
4-Key Enhanced Touch I/O Flash MCU
BS83A04C
4-Key Enhanced Touch I/O Flash MCU
Start
SCL
SDA
SCL
SDA
1 0
ACK Slave Address SRW
Stop
1 1 0 1 0 1 0
1 0 0 1 0 1 0 0
I
2
C time-out
counter start
I
2
C time-out counter reset
on SCL negative transition
I
2
C Time-out
When an I
2
C time-out counter overflow occurs, the counter will stop and the IICTOEN bit will be
cleared to zero and the IICTOF bit will be set high to indicate that a time-out condition has occurred.
The time-out condition will also generate an interrupt which uses the I
2
C interrupt vector. When an
I
2
C time-out occurs, the I
2
C internal circuitry will be reset and the registers will be reset into the
following condition:
Registers After I
2
C Time-out
IICD, IICA, IICC0 No change
IICC1 Reset to POR condition
I
2
C Registers after Time-out
The IICTOF flag can be cleared by the application program. There are 64 time-out periods which
can be selected using IICTOS bit field in the IICTOC register. The time-out time is given by the
formula: [(1~64)×32]/f
SUB
. This gives a time-out period which ranges from about 1ms to 64ms.
• IICTOC Register
Bit 7 6 5 4 3 2 1 0
Name IICTOEN IICTOF IICTOS5 IICTOS4 IICTOS3 IICTOS2 IICTOS1 IICTOS0
R/W R/W R/W R/W R/W R/W R/W R/W R/W
POR 0 0 0 0 0 0 0 0
Bit 7 IICTOEN : I
2
C Time-out control
0: Disable
1: Enable
Bit 6 IICTOF : I
2
C Time-out flag
0: No time-out occurred
1: Time-out occurred
Bit 5~0 IICTOS5~IICTOS0 : I
2
C Time-out period selection
I
2
C time-out clock source is f
SUB
/32.
I
2
C time-out time is equal to (IICTOS[5:0]+1)×(32/f
SUB
).