Datasheet

DIN
DOUT
VBIAS
00100001 00000001
1st
Command
Byte
2nd
Command
Byte
MUX1
DataByte DataByte
DIN
01000010 00000001 MUX2 SYS0
1st
Command
2nd
Command
Data
Byte
Data
Byte
ADS1146
ADS1147
ADS1148
SBAS453F –JULY 2009–REVISED APRIL 2012 www.ti.com
USER REGISTER READ AND WRITE COMMANDS
RREG—Read from registers.
This command outputs the data from up to 16 registers, starting with the register address specified as part of
the instruction. The number of registers read is one plus the second byte. If the count exceeds the remaining
registers, the addresses wrap back to the beginning.
1st Command Byte: 0010 rrrr, where rrrr is the address of the first register to read.
2nd Command Byte: 0000 nnnn, where nnnn is the number of bytes to read –1.
It is not possible to use the full-duplex nature of the SPI interface when reading out the register data. For
example, a SYNC command cannot be issued when reading out the VBIAS and MUX1 data, as shown in
Figure 48. Any command sent during the readout of the register data is ignored. Thus, it is advisable to send
NOP through the DIN when reading out the register data.
Figure 48. Read from Register
WREG—Write to registers.
This command writes to the registers, starting with the register specified as part of the instruction. The
number of registers that are written is one plus the value of the second byte.
1st Command Byte: 0100 rrrr, where rrrr is the address of the first register to be written.
2nd Command Byte: 0000 nnnn, where nnnn is the number of bytes to be written – 1.
Data Byte(s): data to be written to the registers.
Figure 49. Write to Register
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Product Folder Link(s): ADS1146 ADS1147 ADS1148