[AP1021]

015000428-E-00

2015/01

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2. Continuous Data Writing and Reading Mode

Address is incremented automatically and data is written continuously.

When the written address or the

read-out address reaches 03H, it is automatically incremented to 00H.

In this mode, registers are written by 4-wire serial interface pins (CSN, SCK, SDI and SDO). The data on the

4-wire serial interface is 8 bit data, consisting of register address (MSB-first, 7bits), Read/Write and control

or output data (MSB-first, 8xN bits). The receiving data is latched on a rising edge (“”) of SCK. The first

write data becomes effective between the rising edge (“”) and the falling edge (“”) of 16th SCK. When

the micro-processor continues sending SDI and SCK clocks while the CSN pin = “L”, the address counter is

incremented automatically and writing data becomes effective between the rising edge (“”) and the falling

edge (“”) of every 8th SCK. For the last address, writing data becomes effective between the rising edge

(“”) of 8th SCK.

Similarly, in the case of read-out mode, when the micro-processor continues sending SCK clocks while the

CSN pin = “L” the address counter is incremented automatically and the data output from SDO at the falling

edge (“”) of SCK continuously. The clock speed of SCK is 2MHz (max).

Even through the writing data does not reach the last address; a write or read-out command can be completed

when the CSN pin is set to “H” as long as SCK is continuing being inputted.

When CSN “” was written before “” of 8th SCK in continuous data writing mode, the previous data

writing address becomes valid and the writing address is ignored.

After 8bits data in the last address became valid, put the CSN pin “H” to complete the write command. If the

SDI and SCK inputs are continued when the CSN pin = “L”, the data in the next address, which is

incremented, is over written.

CSN

SCK

1

2

3

4

5

6

7

8

9

10

15 16

1

2

SDI

A6 A5

A1

A2

A0

W

A3

D7 D6

D1 D0 D7 D6

A4

7

D1 D0

8

1

2

D7 D6

7

D1

8

D0

Clock,

‘H’ or ‘L’

‘H’ or ‘L’

Clock,

‘H’ or ‘L’

‘H’ or ‘L’

Address: n

Data (Addr: n)

Data (Addr: n+1)

Data (Addr: n+N-1)

A6-A0:

Register Address

R/W:

READ/WRITE (

“0”: WRITE)

D7-D0:

Control data (Input) at Write Command

Figure 6. Serial Control Interface Timing (Continuous Writing Mode)

CSN

SCK

1

2

3

4

5

6

7

8

9

10

15 16

1

2

SDI

A6 A5

A1

A2

A0

R

A3

A4

7

8

1

2

7

8

Clock,

‘H’ or ‘L’

‘H’ or ‘L’

Clock,

‘H’ or ‘L’

‘H’ or ‘L’

Address: n

A6-A0:

Register Address

R/W:

READ/WRITE (

“1”: READ)

D7-D0:

Output data at Read Command (8bit)

SDO

D7 D6

D1 D0 D7 D6

D1 D0

D7 D6

D1 D0

Hi-z

Data (Addr: n)

Data (Addr: n+1)

Data (Addr: n+N-1)

Hi-z

Figure 7. Serial Control Interface Timing (Continuous Reading Mode)