BS85B12-3 HOLTEK [Holtek Semiconductor Inc], BS85B12-3 Datasheet - Page 126

• Manufacturer Part Number: BS85B12-3
• Description: Touch Key Flash Type 8-Bit MCU with LCD/LED Driver
• Manufacturer: HOLTEK [Holtek Semiconductor Inc]

Rev. 1.00
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Name
POR
R/W
Bit
SIMC1 Register
HCF
HCF: I
The HCF flag is the data transfer flag. This flag will be zero when data is being transferred.
Upon completion of an 8-bit data transfer the flag will go high and an interrupt will be generated.
HAAS: I
The HASS flag is the address match flag. This flag is used to determine if the slave device
address is the same as the master transmit address. If the addresses match then this bit will be
high, if there is no match then the flag will be low.
HBB: I
The HBB flag is the I
occur when a START signal is detected. The flag will be set to 0 when the bus is free which will
occur when a STOP signal is detected.
HTX: Select I
TXAK: I
The TXAK bit is the transmit acknowledge flag. After the slave device receipt of 8-bits of data,
this bit will be transmitted to the bus on the 9th clock from the slave device. The slave device
must always set TXAK bit to 0 before further data is received.
SRW: I
The SRW flag is the I
wishes to transmit or receive data from the I
address is match, that is when the HAAS flag is set high, the slave device will check the SRW
flag to determine whether it should be in transmit mode or receive mode. If the SRW flag is high,
the master is requesting to read data from the bus, so the slave device should be in transmit
mode. When the SRW flag is zero, the master will write data to the bus, therefore the slave
device should be in receive mode to read this data.
IAMWU: I
This bit should be set to 1 to enable I
RXAK: I
The RXAK flag is the receiver acknowledge flag. When the RXAK flag is 0 , it means that a
acknowledge signal has been received at the 9th clock, after 8 bits of data have been transmitted.
When the slave device in the transmit mode, the slave device checks the RXAK flag to determine if
the master receiver wishes to receive the next byte. The slave transmitter will therefore continue
sending out data until the RXAK flag is 1 . When this occurs, the slave transmitter will release the
SDA line to allow the master to send a STOP signal to release the I
R
7
1
0: Data is being transferred
1: Completion of an 8-bit data transfer
0: Not address match
1: Address match
0: I
1: I
0: Slave device is the receiver
1: Slave device is the transmitter
0: Slave send acknowledge flag
1: Slave do not send acknowledge flag
0: Slave device should be in receive mode
1: Slave device should be in transmit mode
0: disable
1: enable
0: Slave receive acknowledge flag
1: Slave do not receive acknowledge flag
2
2
C Bus is not busy
C Bus is busy
2
2
C Bus data transfer completion flag
2
C Bus busy flag
C Slave Read/Write flag
2
2
2
C Bus transmit acknowledge flag
C Bus address match flag
C Bus Receive acknowledge flag
2
Touch Key Flash MCU with LCD/LED Driver
C address match wake-up control
HAAS
R
6
0
2
C slave device is transmitter or receiver
2
C busy flag. This flag will be 1 when the I
2
C Slave Read/Write flag. This flag determines whether the master device
HBB
R
5
0
HTX
R/W
120
2
4
0
C address match wake-up from SLEEP or IDLE Mode.
2
C bus. When the transmitted address and slave
TXAK
R/W
3
0
BS85B12-3/BS85C20-3
SRW
2
R
2
0
C bus is busy which will
2
C Bus.
IAMWU
R/W
1
0
February 1, 2011
RXAK
R
0
1