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AS3953

Datasheet - A pp l ic a t io n I n f or m a t i on

more words of data with address auto incrementing (packets of 4 bytes) are transferred to MISO output, always from the MSB to the LSB. MOSI

is sampled at the falling edge of SCLK; data to be read from the AS3953 EEPROM is driven to MISO pin on rising edge of SCLK and is sampled

by the master at the falling edge of SCLK. In case the word on defined address does not exist all ‘0’ data is sent to MISO.

Please note that SCLK frequency should not exceed 1MHz during EEPROM Read (limited by EEPROM read access time).

Figure 10. Reading of EEPROM Page

8.1.4 Loading Transmitting Data into FIFO

Loading the transmitting data into the FIFO is similar to writing data into an addressable registers. Difference is that in case of loading more bytes

all bytes go to the FIFO. The command mode code 10 indicates FIFO operations. In case of loading transmitting data into FIFO all bits

<C5 –

C0> are set to ‘0’. Then a bit-stream, the data to be sent (1 to 32 bytes), can be transferred.

Figure 11 shows how to load the Transmitting data into the FIFO.

Figure 11. Loading of FIFO

8.1.5 Reading Received Data from FIFO

Reading received data from the FIFO is similar to reading data from an addressable registers. Difference is that in case of reading more bytes

they all come from the FIFO. The command mode code 10 indicates FIFO operations. In case of reading the received data from the FIFO all bits

<C5 – C0> are set to ‘1’. On the following SCLK rising edges the data from FIFO appears as in case of read data from addressable registers. In

case the command is terminated by putting /SS high before a packet of 8 bits composing one byte is read that particular byte is considered read.

01 11 1 1 1 1

W

A

4

W

A

3

W

A

2

W

A

1

W

A

0

x

W

A

6

W

A

5

X

MSB Byte from

Address

<WA6-WA0>

/SS

SCLK

MOSI

X

B

2

9

B

2

8

B

2

7

B

2

6

B

2

5

B

2

4

B

3

1

B

3

0

B

2

3

B

2

2

B

5

B

4

B

3

B

2

B

1

B

0

B

7

B

6

B

9

B

8

XX

LSB Byte from

Address

<WA6-WA0>

X

MISO

1µs min

/SS

SCLK

MOSI

1

0000

0

0

0

1 to 32

bytes

X

SCLK rising

edge Data is

transfered

from µC

SCLK falling

edge Data is

sampled

/SS rising edge

signals end of

COMMAND Mode

10 pattern

indicates FIFO

mode

X

Start of

payload Data