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PRELIMINARY
AC97 CONTROLLER
S3C6400 RISC MICROPROCESSOR
35-10
Preliminary product information describe products that are in development,
for which full characterization data and associated errata are not yet available.
Specifications and information herein are subject to change without notice.
Normal
ADCs off
PR0
DACs off
PR1
Analog
off
PR2 or
PR3
Digitial I/F
off
PR4
Shut off
AC-link
Default
PR0 = 1
PR1 = 1
PR2 = 1
PR4 = 1
Warm Reset
PR2 = 0
&
ANL = 1
PR1 = 0
&
DAC = 1
PR0 = 0
&
ADC = 1
Cold Reset
Ready = 1
Figure 35-8 AC97 Power down/Power up Flow
Cold AC97 Reset
A cold reset is generated when the nRESET pin is asserted through the AC_GLBCTRL. Asserting and
deasserting nRESET activates BITCLK and SDATA_OUT. All AC97 control registers are initialized to their default
power on reset values. nRESET is an asynchronous AC97 input.
Warm AC97 Reset
A Warm AC97 reset reactivates the AC-link without altering the current AC97 register values. A warm reset is
generated when BITCLK is absent and SYNC is driven high. In normal audio frames, SYNC is a synchronous
AC97 input. When BITCLK is absent, SYNC is treated as an asynchronous input used to generate a warm reset
to AC97.The AC97 Controller must not activate BITCLK until it samples SYNC low again. This prevents a new
audio frame from being falsely detected.