Datasheet

Data Sheet AD7739
Rev. A | Page 17 of 32
CHANNEL STATUS REGISTERS
8 Bits, Read-Only Registers, Address 0x20 to
Address 0x27, Default Value 0x20 × Channel Number
These registers contain individual channel status information and
some general AD7739 status information (see Table 21 and
Table 22). Reading the status registers can be associated with
reading the data registers in the dump mode. Reading the status
registers is always associated with reading the data registers in the
continuous read mode (see the Digital Interface Description
section for details).
Table 21. Channel Status Registers Bits
Bit Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
Mnemonic
CH2 CH1 CH0 0/P0 RDY/P1 NOREF Sign OVR
Default
Channel number 0 0 0 0 0
Table 22. Channel Status Registers Bit Descriptions
Bit Mnemonic Description
7 to 5 CH2 to CH0 These bits reflect the channel number. This can be used for current channel identification and easier operation
of the dump mode and continuous read mode.
4 0/P0 When the status option bit of the corresponding channel setup register is reset to 0, this bit is read as a 0.
When the status option bit is set to 1, this bit reflects the state of the P0 pin, whether it is configured as an
input or an output.
3 RDY/P1 When the status option bit of the corresponding channel setup register is reset to 0, this bit reflects the
selected channel RDY bit in the ADC status register. When the status option bit is set to 1, this bit reflects the
state of the P1 pin, whether it is configured as an input or an output.
2 NOREF This bit indicates the reference input status. If the voltage between the REFIN(+) and REFIN() pins is less than
NOREF, the trigger voltage, and a conversion is executed, then the NOREF bit goes to 1.
1 Sign This bit reflects the voltage polarity at the analog input. It is 0 for a positive voltage and 1 for a negative voltage.
0 OVR This bit reflects either the overrange or the underrange on the analog input. The bit is set to 1 when the
analog input voltage goes over or under the nominal voltage range (see the Extended Voltage Range of the
Analog Input section).