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AS5013

Datasheet - Detailed Descr i p ti on

Figure 11. Data Write - Slave Receiver Mode



Slave Transmitter Mode (Read Mode): The first byte is received and handled as in the slave receiver mode. However, in this mode, the

direction bit indicates that the transfer direction is reversed. Serial data is transmitted on SDA by the AS5013 while the serial clock is input

on SCL. START and STOP conditions are recognized as the beginning and end of a serial transfer. The slave address byte is the first byte

received after the master generates a START condition. The slave address byte contains the 7-bit AS5013 address. The default address is

80h. The 7-bit slave address is followed by the direction bit (R/W), which, for a read, is 1. After receiving and decoding the slave address

byte the device outputs an acknowledge on the SDA line. The AS5013 then begins to transmit data starting with the register address

pointed to by the register pointer. If the register pointer is not written to before the initiation of a read mode the first address that is read is the

last one stored in the register pointer. The AS5013 must receive a “not acknowledge” to end a read.

Figure 12. Data Read (from Current Pointer Location) - Slave Transmitter Mode

Figure 13. Data Read (from New Pointer Location) - Slave Transmitter Mode

S

1000000

0

A

XXXXXXXX

A

XXXXXXXX

A

XXXXXXXX

NA

S – Start

A – Acknowledge (ACK)

Data transferred: X+1 Bytes + Acknowledge

P – Stop

P

<Slave address>

<Word address (n)>

<Data(n)>

<Data(n+X)>

XXXXXXXX

A

<Data(n+1)>

S

1000000

1

A

XXXXXXXX

A

XXXXXXXX

A

XXXXXXXX

NA

S – Start

A – Acknowledge (ACK)

Data transferred: X+1 Bytes + Acknowledge

NA – Not Acknowledge (NACK)

Note: Last data byte is followed by NACK

P – Stop

P

<Slave address>

<Data(n)>

<Data(n+1)>

<Data(n+X)>

XXXXXXXX

A

<Data(n+2)>

S

1000000

0 A

XXXXXXXX

A

1000000

1

XXXXXXXX

A

S – Start

SA – Repeated Start

A – Acknowledge (ACK)

Data transferred: X+1 Bytes + Acknowledge

NA – Not Acknowledge (NACK)

Note: Last data byte is followed by NACK

P – Stop

P

<Slave address>

<Word Address (n)>

<Slave Address>

<Data(n+1)>

XXXXXXXX

A

<Data(n)>

Sr

A

XXXXXXXX

NA

<Data(n+X)>