HT46RU22 Holtek Semiconductor Inc., HT46RU22 Datasheet - Page 27

• Manufacturer Part Number: HT46RU22
• Description: Ht46ru22 -- A/d Type 8-bit Mcu
• Manufacturer: Holtek Semiconductor Inc.

Acknowledge Bit
One of the slave device generates an acknowledge sig-
nal, when the slave address is matched. The master de-
vice can check this acknowledge bit to know if the slave
device accepts the calling address. If no acknowledge
bit, the master must send a STOP bit and end the com-
munication. When the I
HAAS is high, it means the address is matched, so the
slave must check SRW as a transmitter (set HTX) to 1
or as a receiver (clear HTX) to 0 .
Data Byte
The data is 8 bits and is sent after the slave device has
acknowledges the slave address. The first bit is MSB
and the 8th bit is LSB. The receiver sends the acknowl-
edge signal ( 0 ) and continues to receive the next 1
byte data. If the transmitter checks and there s no ac-
knowledge signal, then it release the SDA line, and the
Rev. 1.20
Stop Bit
2
C Bus status register bit 6
27
master sends a STOP signal to release the I
data is stored in the HDR register. The transmitter must
write data to the HDR before transmit data and the re-
ceiver must read data from the HDR after receiving
data.
Receive Acknowledge Bit
When the receiver wants to continue to receive the next
data byte, it generates an acknowledge bit (TXAK) at
the 9th clock. The transmitter checks the acknowledge
bit (RXAK) to continue to write data to the I
change to receive mode and dummy read the HDR reg-
ister to release the SDA line and the master sends the
STOP signal.
Data Timing Diagram
HT46RU22
March 23, 2007
2
C Bus. The
2
C Bus or