Renesas SH7781 - Manual (Page 1293)

25. Audio Codec Interface (HAC)
Rev.1.00 Jan. 10, 2008 Page 1263 of 1658
REJ09B0261-0100
Section 25 Audio Codec Interface (HAC)
The HAC, the audio codec digital controller interface, supports a subset of Audio Codec 97
(AC'97) Version 2.1. The HAC provides serial transmission to/reception from the AC97 codec.
Each channel of the HAC can be connected to a single audio codec device.
The HAC carries out data extraction from/insertion into audio frames. For data slots within both
receive and transmit frames, the PIO transfer by the CPU or the DMA transfer by the DMAC can
be used.
25.1 Features
The HAC has the following features:
• Supports a subset of digital interface to a single AC'97 revision 2.1 Audio Codec
• PIO transfer of status slots 1 and 2 in RX frames
• PIO transfer of command slots 1 and 2 in TX frames
• PIO transfer of data slots 3 and 4 in RX frames
• PIO transfer of data slots 3 and 4 in TX frames
• Selectable 16-bit or 20-bit DMA transfer of data slots 3 and 4 in RX frames
• Selectable 16-bit or 20-bit DMA transfer of data slots 3 and 4 in TX frames
• Accommodates various sampling rates by qualifying slot data with tag bits and monitoring the
TX frame request bits of RX frames
• Generates data ready, data request, overrun and underrun interrupts
• Supports cold reset, warm reset, and power-down mode