Cirrus Logic CS5464 - Manual (Page 24)

CS5464
24 DS682F3
7.6 Commands
All commands are 1 byte (8 bits) long. Many command values are unused and should NOT be written by the
application program. All commands except register reads, register writes, or synchronizing commands will
abort any conversion, calibration, or any initialization sequence currently executing. This includes reset. No
commands other than reads or synchronizing should be executed until the reset sequence completes.
7.6.1 Conversion
Executes a conversion (measurement) program.
CC Continuous/Single Conversion
0 = Perform a Single Conversion (0xE0)
1 = Perform Continuous Conversion (0xE8)
7.6.2 Synchronization (SYNC0 and SYNC1)
The serial interface is bidirectional. While reading data on the SDO output, the SDI input must be receiving
commands. If no command is needed during a read, SYNC0 or SYNC1 commands can be sent while read
data is received on SDO.
The serial port is normally initialized by de-asserting CS. An alternative method of initialization is to send 3 or
more SYNC1 commands followed by a SYNC0. This is useful in systems where CS is not used and tied low.
7.6.3 Power Control (Stand-by, Sleep, Wake-up/Halt and Software Reset)
The CS5464 has two power-down states, stand-by and sleep. In stand-by, all circuitry except the voltage ref-
erence and clocks are turned off. In sleep, all circuitry except the command decoder is turned off. A
Wake-up/Halt command restores full-power operation after stand-by and issues a hardware reset after sleep.
The Software Reset command is a program that emulates a pin reset and is not a power control function.
S[1:0] 00 = Software Reset
01 = Sleep
10 = Wake-up/Halt
11 = Stand-by
B7 B6 B5 B4 B3 B2 B1 B0
1 1 1 0 CC 0 0 0
B7 B6 B5 B4 B3 B2 B1 B0
1 1 1 1 1 1 1 SYNC
B7 B6 B5 B4 B3 B2 B1 B0
1 0 S1 S0 0 0 0 0