alc260d-ve-lf Realtek Semiconductor Corporation, alc260d-ve-lf Datasheet - Page 22

• Manufacturer Part Number: alc260d-ve-lf
• Description: 2 Channel High Definition Audio Codec
• Manufacturer: Realtek Semiconductor Corporation

7.3.1.
A link reset may be caused by 3 events:
1.
2.
3.
Enter ‘Link Reset’:
Exit from ‘Link Reset’:
2 Channel High Definition Audio Codec
SYNC
BCLK
SDOs
RST#
SDIs
Software writes a 0 to the ‘CRST’ bit in the Global Control Register of the HDA controller to initiate a
As the controller completes the current frame, it does not signal the normal 8-bit frame SYNC at the end
The controller drives SYNC and all SDOs to low. Codecs also drive SDIs to low
The controller asserts the RST# signal to low, and enters the ‘Link Reset’ state
All link signals driven by controller and codecs should be tri-state by internal pull low resistors
BCLK is re-started for any reason (codec wake-up event, power management, etc.)
Minimum of 4 BCLK after RST# is de-asserted, the controller starts to signal normal frame SYNC
When the codec drives it’s SDI to request an initialization sequence (when the SDI is driven high at the
link reset
of the frame
100µsec provides time for the codec PLL to stabilize)
last bit of frame SYNC), it means the codec requests an initialization sequence)
Software is responsible for de-asserting RST# after a minimum of 100µsec BCLK running time (the
The HDA controller asserts RST# for any reason (power up, or PCI reset)
Software initiates a link reset via the ‘CRST’ bit in the Global Control Register (GCR) of the HDA
controller
Software initiates power management sequences. Figure 11, page 15, shows the ‘Link Reset’ timing
including the ‘Enter’ sequence ( ~ ) and ‘Exit’ sequence ( ~ )
Link Reset
1
2
SYNC is absent
Previous Frame
Normal Frame
3
Driven Low
Driven Low
Driven Low
4 BCLK
Figure 11. Link Reset Timing
4
4 BCLK
15
5
Pulled Low
Pulled Low
Pulled Low
Pulled Low
Link in Reset
6
>=100 usec
Track ID: JATR-1076-21 Rev. 1.4
7
>= 4 BCLK
Wake Event
8
Initialization Sequence
Normal Frame
SYNC
ALC260(D)
Datasheet
9