HMC5983-DEM Datasheet, PDF (25/28 Pages) Honeywell Accelerometers – 3-Axis Digital Compass IC

HMC5983
The SPI Write command is performed with 16 clocks pulses. Multiple byte write command is performed adding blocks of 8
clocks pulses at the previous one.
bit 0: WRITE bit. The value is 0.
bit 1: MS bit. When 0 do not increment address, when 1 increment address in multiple writing.
bit 2 -7: address AD(5:0). This is the address field of the indexed register.
bit 8-15: data DI(7:0) (write mode). This is the data that will be written inside the device (MSb first).
bit 16-... : data DI(...-8). Further data in multiple byte writing.
Figure 5: Multiple bytes SPI Write Protocol (2 bytes example)
SPI Read in 3-wires mode
3-wires mode is entered by setting to 1 bit SIM (SPI Serial Interface Mode selection) in MODE_REG(2).
Figure 6: SPI Read Protocol in 3-wires Mode
The SPI Read command is performed with 16 clocks pulses:
bit 0: READ bit. The value is 1.
bit 1: MS bit. When 0 do not increment address, when 1 increment address in multiple reading.
bit 2-7: address AD(5:0). This is the address field of the indexed register.
bit 8-15: data DO(7:0) (read mode). This is the data that will be read from the device (MSb first).
Multiple write command is also available in 3-wires mode.
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