TC35679FSG-002

2018-01-17

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4.5.4.

Frame Format

For I2C format, TC35679 first generates start condition. Then, it sends device recognition address (7 bit: [A6:A0]) and the first byte

address ([B7:B0]) for the access target. Next, it goes for read or write sequence. For I2C, every data is sent as MSB first. How to

specify the value and byte address of the device identification address, and it has been determined in accordance with the device

to be connected. In order to be connected, it must match the device to be connected. For read operation, TC35679 returns to the

serial memory either receive acknowledge bit (ACK) or receive not acknowledge bit (NACK) every time it receives one byte. For

write operation, TC35679 receives either ACK or NACK from the serial memory every time it sends one byte. It can handle not only

one byte but also several bytes in a row. TC35679 generates stop condition when it has finished all the read or write of data.

Figure 4-16 shows an example where TC35679 reads two-byte data. Figure 4-17 shows an example where TC35679 writes

two-byte data. In these examples, gray texts and lines indicate signals that are given by the serial memory. For read operation, after

having read the final byte data, TC35679 returns NACK with which the serial memory gets to know the completion of the read

operation.

Figure 4-16 I

2

C format (Serial memory, read)

Figure 4-17 I

2

C format (Serial memory, write)

Serial

clock

A6

MSB LSB

Serial

data

Start condition

A0

B0

W

ACK

ACK

D7

D0

LSB

MSB

B7

MSB LSB

ACK

Stop condition

D7

D0

LSB

MSB

ACK

Serial

clock

A6

MSB LSB

Start condition

A0

B0

W

ACK

ACK

A6

D7

D0

LSB

MSB

A0

LSB

MSB

B7

MSB LSB

R ACK

NAC

Stop condition

D7

D0

LSB

MSB

ACK

Start condition

Serial

data