Datasheet

ADS1259
SBAS424D –JUNE 2009– REVISED AUGUST 2011 www.ti.com
COMMAND DEFINITIONS
The commands summarized in Table 19 control and configure the operation of the ADS1259. The commands
are stand-alone, except for the register read and register write operations which require a second command byte
plus data. CS can be taken high or held low between opcode commands but must stay low for the entire
command operation. Note that the Read Data Continuous mode must be cancelled by the Stop Read Data
Continuous mode opcode (SDATAC) before sending further commands.
Table 19. Command Definitions
(1)
COMMAND TYPE DESCRIPTION FIRST OPCODE BYTE SECOND OPCODE BYTE
WAKEUP Control Wake up from SLEEP mode 0000 001x (02h or 03h)
(2)
SLEEP Control Begin SLEEP mode 0000 010x (04h or 05h)
(2)
RESET Control Reset to power-up values 0000 011x (06h or 07h)
(2)
START Control START conversion 0000 100x (08h or 09h)
(2)
STOP Control STOP conversion 0000 101x (0Ah or 0Bh)
(2)
RDATAC Control Set Read Data Continuous mode 0001 0000 (10h)
SDATAC Control Stop Read Data Continuous mode 0001 0001 (11h)
RDATA Data Read data by opcode 0001 001x (12h or 13h)
(2)
RREG Register Read nnnn register at address rrrr 0010 rrrr (20h + 0000 rrrr) 0000 nnnn (00h + nnnn)
WREG Register Write nnnn register at address rrrr 0100 rrrr (40h + 0000 rrrr) 0000 nnnn (00h + nnnn)
OFSCAL Calibration Offset calibration 0001 1000 (18h)
GANCAL Calibration Gain calibration 0001 1001 (19h)
(1) nnnn = number of registers to be read/written – 1. For example, to read/write 3 registers, set nnnn = 2 (0010).
rrrr = starting register address for read/write opcodes.
(2) These commands are decoded on the seventh bit of the opcode. The eighth bit is a don't care bit. All other commands are decoded on
the eighth bit.
WAKEUP: Exit SLEEP Mode
Description: This command exits the low-power SLEEP mode; see the SLEEP Mode section.
SLEEP: Enter SLEEP Mode
Description: This command enters the low-power SLEEP mode. See the SLEEP Mode section.
RESET: Reset Registers to Default Values
Description: This command resets the digital filter cycle and returns all register settings to the default values.
START: Start Conversions
Description: This command starts data conversions. If PULSE bit = 1, then a single conversion is performed. If
PULSE bit = 0, then conversions continue until the STOP command is sent. Tie the START pin low to control
conversions by command.
STOP: Stop Conversions
Description: This command stops conversions. When the STOP command is sent, the conversion in progress
completes and further conversions are stopped. If conversions are already stopped, this command has no effect.
See the Conversion Control section. Tie the START pin low to control conversions by command.
RDATAC: Read Data Continuous
Description: This command enables the Read Data Continuous mode (default). See the Read Data Continuous
Mode section for details. Disable this mode with the SDATAC command before sending other commands.
SDATAC: Stop Read Data Continuous
Description: This command cancels the Read Data Continuous mode.
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