Cirrus Logic CS5528 - Manual (Page 18)

CS5521/22/23/24/28
18 DS317F8
1.2.1 System Initialization
After power is first applied to the
CS5521/22/2324/28 devices, the user should wait
for the oscillator to start before attempting to com-
municate with the converter. If a 32.768 kHz crys-
tal is used, this may be 500 milliseconds.
The initialization sequence should be as follows:
Initialize the serial port by sending the port initial-
ization sequence of 15 bytes of all 1's followed by
one byte with the following bit contents '1111 110'.
This sequence places the chip in the command
mode where it waits for a valid command to be
written. The first command should be to perform a
system reset. This is accomplished by writing a
logic 1 to the RS (Reset System) bit in the configu-
ration register. After a reset the RV bit is set until
the configuration register is read. The user must
then write a logic 0 to the RS bit to take the part out
of reset mode. Any other bits written to the config-
uration register at this time will be lost. The con-
figuration register must be written again once RS=
0 to set any other bits to their desired settings.
After a reset, the on-chip registers are initialized to
the following states:
configuration register: 000040(H)
offset registers: 000000(H)
gain registers: 400000(H)
channel setup registers: 000000(H)