Datasheet ADS1015

Frame 1: Slave Address Byte
Frame 2: Address Pointer Register
1
Start By
Master
ACK By
ADS1013/4/5
ACK By
ADS1013/4/5
Frame 3: Slave Address Byte
Frame 4: Data Byte 1 Read Register
Start By
Master
ACK By
ADS1013/4/5
ACK By
Master
(2)
From
ADS1013/4/5
1 9 1
9
1 9 1
9
SDA
SCL
0 0 1 R/W
0 0 0 0 0 0 P1 P0
¼
¼
¼
SDA
(Continued)
SCL
(Continued)
SDA
(Continued)
SCL
(Continued)
1 0 0 1
0 A1
(1)
A0
(1)
0
A1
(1)
A0
(1)
R/W D15 D14 D13 D12 D11 D10 D9 D8
Frame 5: Data Byte 2 Read Register
Stop By
Master
ACK By
Master
(3)
From
ADS1013/4/5
1
9
D7 D6 D5 D4 D3 D2 D1 D0
Stop By
Master
20
ADS1013 , ADS1014 , ADS1015
SBAS473E –MAY 2009–REVISED JANUARY 2018 www.ti.com
Product Folder Links: ADS1013 ADS1014 ADS1015
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8.5.3 Writing To and Reading From the Registers
To access a specific register from the ADS101x, the master must first write an appropriate value to register
address pointer bits P[1:0] in the Address Pointer register. The Address Pointer register is written to directly after
the slave address byte, low R/W bit, and a successful slave acknowledgment. After the Address Pointer register
is written, the slave acknowledges, and the master issues a STOP or a repeated START condition.
When reading from the ADS101x, the previous value written to bits P[1:0] determines the register that is read. To
change which register is read, a new value must be written to P[1:0]. To write a new value to P[1:0], the master
issues a slave address byte with the R/W bit low, followed by the Address Pointer register byte. No additional
data has to be transmitted, and a STOP condition can be issued by the master. The master can now issue a
START condition and send the slave address byte with the R/W bit high to begin the read. Figure 22 details this
sequence. If repeated reads from the same register are desired, there is no need to continually send the Address
Pointer register, because the ADS101x store the value of P[1:0] until it is modified by a write operation. However,
for every write operation, the Address Pointer register must be written with the appropriate values.
(1) The values of A0 and A1 are determined by the ADDR pin.
(2) Master can leave SDA high to terminate a single-byte read operation.
(3) Master can leave SDA high to terminate a two-byte read operation.
Figure 15. Timing Diagram for Reading From ADS101x