Datasheet

AD7280A
Rev. 0 | Page 42 of 48
Example 5: Read a Single Configuration Register
on All Parts
In this example, it is assumed that all AD7280As in the daisy
chain have been initialized to their correct device addresses.
1.
Set Bit D0 of the control register to 1 on all parts. This write
enables the daisy-chain register read operation on all parts.
The 32-bit write command is 0x01C2B6E2 (see Table 27 ,
Write 1).
2.
The register address corresponding to the configuration
register to be read should be written to the read register on
all parts (see Table 13 for register addresses). In this example,
the cell balance register is read from all parts. The 32-bit
write command is 0x038A12B2 (see Table 27, Write 2).
3.
Apply a
CS
low pulse that frames 32 SCLKs for each device
in the stack to read back the desired register contents from
all parts. This frame should simultaneously write the 32-bit
command 0xF800030A, as described in the
section (see , Write 3).
Serial Interface
Table 27
Example 6: Read a Single Configuration Register
from One Part
In this example, it is assumed that all AD7280As in the daisy
chain have been initialized to their correct device addresses.
1.
Set Bits[D13:D12] of the control register to 1 on all parts.
This setting turns off the read operation on all parts. The
32-bit write command is 0x01A6151A (see Table 28, Write 1).
2.
Set Bits[D13:D12] of the control register of the part to be
read from to 0. In this example, Device 1 in the stack is to
be read from. The 32-bit write command is 0x81A00222
(see Table 28, Write 2).
3.
The register address corresponding to the configuration
register to be read should be written to the read register of
the part that is to be read (see Table 13 for register
addresses). This example reads the alert register from
Device 1 in the stack. The 32-bit write command is
0x8389800A (see Table 28, Write 3).
4.
Apply a
CS
low pulse that frames 32 SCLKs to read back
the desired register contents. This frame should simultan-
eously write the 32-bit command 0xF800030A, as
described in the section (see ,
Write 4). When reading from a single device in a stack of
AD7280As, the SCLK frequency must be lower than
1 MHz to read back the register data from parts higher in
the chain than the master device.
Serial Interface Table 28
Table 27. Example 5: Reading a Single Configuration Register from All AD7280A Devices
Write Command Device Address Register Address Data Write All D11 8-Bit CRC D2 to D0
32-Bit Write
Command
Write 1 00000 001110 00010101 1 0 11011100 010 0x01C2B6E2
Write 2 00000 011100 01010000 1 0 01010110 010 0x038A12B2
Write 3 11111 000000 00000000 0 0 01100001 010 0xF800030A
Table 28. Example 6: Reading a Single Configuration Register from One AD7280A Device
Write Command Device Address Register Address Data Write All D11 8-Bit CRC D2 to D0
32-Bit Write
Command
Write 1 00000 001101 00110000 1 0 10100011 010 0x01A6151A
Write 2 10000 001101 00000000 0 0 01000100 010 0x81A00222
Write 3 10000 011100 01001100 0 0 00000001 010 0x8389800A
Write 4 11111 000000 00000000 0 0 01100001 010 0xF800030A