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AS1130

Datasheet - D e t a i l e d D e s c r i p t i o n

Figure 22. Reading n Bytes from AS1130

I²C Device Address Byte

The address byte (see Figure 23) is the first byte received following the START condition from the master device.

Figure 23. I²C Device Address Byte

- The bit 1, 2 and 3 of the address byte are defined through the resistor @ the device select pin ADDR (see Table 6 on page 12). A

maximum of 8 devices with the same pre-set code can be connected on the same bus at one time.

- The last bit of the address byte (R/W) define the operation to be performed. When set to a 1 a read operation is selected; when set to a 0

a write operation is selected.

- I²C Common address. All devices are responding on the address “0111111” if the function is enabled in the register AS1130 Config

Register (0x06) on page 25

.

Following the START condition, the AS1130 monitors the I²C bus, checking the device type identifier being transmitted. Upon receiving the

address code, and the R/W bit, the slave device outputs an acknowledge signal on the SDA line.

The pin ADDR is scanned after start up (POR) and defines the address for the device. The device reacts to this address until a hardware reset

(low on pin RSTN) is performed or the power-on-reset (POR) triggers again.

Note:

The internal address decoder needs 5ms to identify the address and to set up the device for this address.

Table 6. Device Address

I2C Address

Bit

Bit Name

Default

Access

Description

3:1

i2c_addr

000

R

Defines the I²C address of one device via an external resistor on pin ADDR

000: 1M

Ω or floating

001: 470k

Ω

010: 220k

Ω

011: 100k

Ω

100: 47k

Ω

101: 22k

Ω

110: 10k

Ω

111: 4.7k

Ω or GND

From Master to Slave

From Slave to Master

A

/A

P

A

S

First Data Byte

Second Data Byte

Slave Address

D6

D5

D4

D3

D2

D1

D0

D7

D6

D5

D4

D3

D2

D1

D0

D7

Not Acknowledge

from Master

0

1

0

Acknowledge

from Master

Acknowledge

from AS1130

R/W

1

AS1130 Registers

Autoincrement

Memory Word

Address

n Bytes

Autoincrement

to next address

Stop reading

0

1

1

0*

AD2

AD1

AD0

R/W

MSB

6

5

4

3

2

1

LSB

address:

*) can be factory set to 1