- Hd Audio Connector Motherboard
- Front Panel Audio Header
- What Is Ac97 Front Panel
- Ac97 Front Panel Vs Hd Audio Front Panel
Intel High Definition Audio (IHDA) (also called HD Audio or development codename Azalia) is a specification for the audio sub-system of personal computers. It was released by Intel in 2004 as successor to its AC'97 PC audio standard.[1]
The front panel is AC97 and it was set to AC97 in the BIOS, but Windows 10 would still think it is HD audio and try to do headphone detection, which will not work with an AC97 plug. I had to install the Realtek drivers and force it to AC97 using the utility.
The solution to all of this of course is to get a HD Audio front panel connector. Most cases don't have it for some unknown reason but the Silverstone FP32 is a front connector panel that fits in a 3 1/2' drive bay. HD Audio in the front and AC97 in the rear, HD Audio is the front panel. Some mainboards will let you switch what the front panel is in the bios. The M3N78 Pro does for example. I believe the big difference in hd audio and ac97 connectors is that HD audio can support 8 channels, thus why the connector is bigger. The rear panel audio output jacks are disabled when headphones are plugged in. This feature is implemented through the front panel audio header shown in Figure 3 and Table 6. If the front panel interface board is not connected to the front panel audio header, jumpers should be installed across header pin pairs 1-2, 3-4, 5-6, and 9-10.
Features[edit]
The Intel High Definition Audio specification includes the following features:[2]
- Up to 15 input and 15 output streams
- Up to 16 PCM audio channels per stream
- Sample resolutions of 8–32 bits
- Sample rates of 6–192 kHz
- Support for audio codecs (e.g., ADC, DAC), modem codecs, and vendor-defined codecs
- Discoverable codec architecture
- Fine-grained codec power-control
- Audio jack detection, sensing, and retasking
However, as of 2008, most audio hardware manufacturers did not implement the full specification, especially 32-bit sampling resolution.[citation needed] Motherboards typically do not have any more than eight onboard output channels (7.1 surround sound) and four input channels (back and front panel microphone inputs, and a back-panel stereo line-in). Users requiring more audio I/Os will typically opt for a sound card or an external audio interface, as these devices also provide additional features that are more oriented towards professional audio applications.
Operating system support[edit]
MicrosoftWindows XP SP3 and later Windows versions[3] include a Universal Audio Architecture (UAA) class driver which supports audio devices built to the HD Audio specification. There are UAA drivers for Windows 2000 and Windows XP SP2 as well. macOS has full support with its AppleHDA driver. Linux also supports HD Audio controllers, as do the OpenSolaris,[4]FreeBSD,[5]NetBSD and OpenBSD[6] operating systems. However, it was first introduced in Windows XP x64 Edition and Windows Server 2003 x64 Edition with Service Pack 1. It had problems in some computers that have HD Audio in the motherboard chipset. This was fixed with Service Pack 2 for Windows Server 2003 x64 and Windows XP Professional x64 Edition.
Hd Audio Connector Motherboard
Host controller[edit]
Like AC'97, HD Audio is a specification that defines the architecture, link frame format, and programming interfaces used by the controller on the PCI bus and by the codec on the other side of the link. Implementations of the host controller are available from at least Intel, Nvidia, and AMD.[7] Codecs which can be used with such controllers are available from many companies, including Realtek,[8]Conexant (including products of acquired Analog Devices' SoundMAX division),[9] Tempo Semiconductor, VIA, Wolfson Microelectronics, and formerly C-Media. Realtek currently supplies most of HD Audio codec chips used on motherboards and standalone cards.
Nearly all chipsets for x86 processors and x86 SoCs, designed for consumer and embedded PC markets, introduced since 2005, implements integrated HD Audio controller. The most recent exemption in consumer chipset market is AMD TRX40 (launched 2019), which, for first time since the early 2000s, does not itself integrate any kind of audio controller. Instead, motherboard manufacturers places USB audio controller chip, in pair with usual HD Audio codec chip, to provide onboard audio functionality. The Realtek ALC4050H controller and ALC1220 codec is the most common pair used in sTRX4 motherboards.
Front panel connector[edit]
Computer motherboards often provide a connector to bring microphone and headphone signals to the computer's front panel. Intel provides a specification for that header, but the signal assignments are different for AC'97 and HD Audio headers.[10]
The pin assignments for the AC'97 and HD Audio connectors are:[10]
| Pin | AC'97 | HD Audio (HDA) | ||
|---|---|---|---|---|
| Signal | Description | Signal | Description | |
| 1 | MIC |
| PORT 1L | Audio, left, port 1 |
| 2 | AUD_GND | Ground | GND | Ground |
| 3 | MIC BIAS |
| PORT 1R | Audio, right, port 1 |
| 4 | AUD_GND | Ground | PRESENCE# | HDA dongle/connector detection, active low |
| 5 | FP_OUT_R | Audio out, right, out (headphone-level capable), front panel | PORT 2R | Audio, right, port 2 |
| 6 | FP_RETURN_R | Audio, right, return (when jack is unconnected), front panel | SENSE1_RETURN | Port 1 jack detection |
| 7 | AUD_5V | Power, +5 V | SENSE_SEND | Jack detection sense, resistance multiplexed |
| 8 | KEY | Not present, physical key | KEY | Not present, physical key |
| 9 | FP_OUT_L | Audio, left, out (headphone-level capable), front panel | PORT 2L | Audio, left, port 2 |
| 10 | FP_RETURN_L | Audio, left, return (when jack is unconnected), front panel | SENSE2_RETURN | Port 2 jack detection |
The HDA 3.5 mm subminiature audio connectors differ from connectors used in the AC'97 specification and general audio equipment. A regular 3.5 mm audio jack (which is used in AC'97) typically has 5 pins: one pin for ground, two pins for stereo signal and two pins for return signal.[11] When there is no plug in the jack, the two stereo signals are connected to their return pins. When a plug is inserted, the stereo signals contact the respective channels on the plug and are disconnected from the jack's return pins. The HDA 3.5 mm jack does not have the two return audio signals; instead it has an isolated switch that senses the presence of a plug in the jack.[12]
In the AC'97 design, the audio output is always sent to the jack. If the headphones are not plugged in, the jack directs the audio to the return pins that are connected to the speakers. When a headphone is plugged into the front panel jack, the audio signal goes to the headphones; the return pins are disconnected, so no audio signal goes to the speakers. For the microphone jack, the return signal pins ground the microphone input when the microphone is not plugged in. Wwe smackdown vs raw 2009 pc game download rar. Many motherboards with AC'97 audio need two jumpers to short the pins in case no front panel audio module is connected, so audio passes to the speakers.[13]
In the HDA design, when the plug is not inserted, the codec sends the audio directly to the speakers (the audio does not go out to the front panel and then loop back to the speakers). When the plug is inserted, the isolated switch inside the jack informs the motherboard, and the codec sends audio to the headphones. A similar isolated switch is used to detect when a microphone has been plugged in.
HD Audio can sense the presence of an audio dongle.[14] A 10 kΩ pull-up resistor is attached to pin 4 (PRESENCE#). When the HDA dongle is plugged in, it pulls pin 4 to ground with a 1 kΩ resistor. The motherboard can determine if the dongle is plugged in by examining the logic level on pin 4. If the motherboard does not detect the presence of an HDA dongle, then it should ignore SENSE1_RETURN (pin 6) and SENSE2_RETURN (pin 10) signals. In AC'97, pins 2 and 4 are audio ground, but pin 4 is often disconnected. Consequently, an HDA motherboard would not detect the presence of an AC'97 dongle with a disconnected pin 4.
Intel warns that HDA dongles should be used with HDA motherboards:[15]
It is strongly recommended that motherboard designers only use Intel HD Audio analog front panel dongles with the Intel HD Audio analog front panel header to insure that the jack detection and dynamic re-tasking capability is preserved. Passive AC'97 analog front panel dongles (ones which leave the 5V Analog pin-7 line unconnected on the dongle) may be used with the Intel HD Audio analog front panel header. But note that the front panel jack detection and re-tasking functionality will be lost as the AC'97 jacks cannot support connection to the SENSE line. In addition, software must be aware that an AC'97 dongle is being used with an Intel HD Audio analog header since the software might need to dedicate codec ports that are connected to the header to meet the product's intended functionality.
The different signal assignments can cause trouble when AC'97 front-panel dongles are used with HDA motherboards and vice versa. An AC'97 dongle returns audio on pins 6 and 10 rather than a digital plug sensing signals. Consequently, a loud audio passage may make the HDA motherboard with AC'97 dongle believe that headphones and microphones are being plugged and unplugged hundreds of times per second. An AC'97 motherboard with an HDA dongle will route the AC'97 5 V audio supply (pin 7; silence) to the speakers instead of the desired left and right audio signals.
To avoid this, some motherboards allow choosing between HDA and AC'97 front panels in the BIOS. Even though the actual audio hardware is HD Audio, it will allow using the AC'97 front panel that way. Likewise, some modern enclosures have both an 'AC'97' and an 'HDA' plug at the end of the front-panel audio cable.
See also[edit]
References[edit]
- ^Smith, Tony (16 April 2004). 'Intel completes hi-def audio spec'. The Register. Situation Publishing Limited. Retrieved 14 January 2014.
- ^'High Definition Audio Specification 1.0a'(PDF). Intel Corporation. 2010. p. 17.
- ^Microsoft Knowledge Base Article 888111
- ^OpenSolaris Boomer Project Page, 2009
- ^snd_hda. Man.freebsd.org (2012-01-25). Retrieved on 2013-07-28.
- ^Manual Pages: azalia. OpenBSD.org (2012-03-15). Retrieved on 2018-02-03.
- ^AMD SB600 Product Information Page, 2009
- ^ALC888 Product Page, 2009
- ^Conexant - PC HD-AudioArchived 2013-08-19 at the Wayback Machine
- ^ abIntel Corporation (February 2005), Front Panel I/O Connectivity Design Guide(PDF), Version 1.3, pp. 19–25, archived from the original(PDF) on 2011-05-11, retrieved 2011-11-04
- ^Intel Corporation 2005, p. 20
- ^Intel Corporation 2005, p. 25
- ^Intel Corporation 2005, p. 21
- ^Intel Corporation 2005, p. 24
- ^Intel Corporation 2005, p. 19
External links[edit]
- High Definition Audio Specification 1.0a (June 17, 2010)
AC'97 (Audio Codec '97; also MC'97 for Modem Codec '97) is an audiocodec standard developed by Intel Architecture Labs in 1997. The standard was used in motherboards, modems, and sound cards.
The specification covers two types of component, and the 'AC-link' digital interface between them:
- an AC'97 digital controller (DC97), which is built into the southbridge of the chipset, and
- an AC'97 audio and modem codec, available from several vendors, which contains the analog components of the architecture.
AC'97 defines a high-quality, 16- or 20-bit audio architecture with 5.1 surround sound support for the PC. AC'97 supports a 96 kHz sampling rate at 20-bit stereo resolution and a 48 kHz sampling rate at 20-bit stereo resolution for multichannel recording and playback.
Integrated audio is implemented with the AC'97 Codec on the motherboard, a Communications and Networking Riser card, or an audio/modem riser card.
In 2004, Intel released Intel High Definition Audio (HD Audio) which is a successor that is not backward compatible with AC'97.[1] HD Audio has the capability to define up to 15 output channels, but in practice most motherboards provide no more than 8 channels (7.1 surround sound).
Revisions[edit]
AC'97 has had several revisions:[2]
- AC'97 1.x compliant indicates fixed 48K sampling rate operation (non-extended feature set)
- AC'97 2.1 compliant indicates extended audio feature set (optional variable rate, multichannel, etc.)
- AC'97 2.2 compliant indicates extended audio, enhanced riser audio support, and optional Sony/Philips Digital Interface Format
- AC'97 2.3 compliant indicates extended configuration information and optional jack sensing support
AC'97 revision 2.3 enables Plug and Play for the end user. This revision provides means for the audio codec to supply parametric data about its analog interface much like Intel High Definition Audio.
AC-Link[edit]
The AC-Link is a digital link that connects the DC97 (the controller) with the audio 'codecs.' It is composed of five wires: the 12.288 MHz clock, a 48 kHz sync signal, a reset signal, and two data wires which carry the actual audio data: sdata_out and sdata_in. The first four are outputs from the controller, while sdata_in carries input from the codec. The link carries a bidirectional serial data stream at a fixed bitrate (12.288 Mbit/s) between the controller and one or more codecs.
Front Panel Audio Header
Each 12.288 Mbit/s stream is divided into 256-bit frames (frame frequency is 48 kHz). This is therefore a time-division multiplexing scheme.
Every frame is subdivided in 13 slots. The first (slot 0) is 16 bits long and contains validity flags for the remaining slots, while the remaining 240 bits are divided in twelve 20-bit slots (slots 1–12), used as data slots.
Slots 1, 2 and 12 are used for non-audio data, while slots 3–11 carry up to nine channels of raw pulse-code modulation audio signals. Normally, six channels are used for 5.1 surround sound, and three channels are available for modem use. However, slots can be combined to provide a 96 kHz sampling rate for the L, R and C channels.
Lower sample rates (such as 44.1 kHz) are implemented using a handshake protocol between the controller and codec which skips data during certain frames. (This capability depends on the codec. Mafia 2 free download. Alternatively, sample rate conversion could be performed in the DC97 (controller) or in the software driver.)
Codec chips[edit]
Codec chips have an AC'97 interface on one side and analog audio interface on the other. They are usually small square chips with 48 pins (48-pin QFP package). They are D/A and A/D or only D/A.
- Analog Devices AD1819B, 1881A, 1885, 1886, 1887, 1980, 1981, 1985
- AKM (Asahi Kasei Microsystems) AK 4540, 4543, 4544A, 4545
- Avance Logic (now Realtek) ALC201A, ALC202/A, ALC650, ALC655, ALC658, ALC101, ALC202A, ALC250, ALC850, ALC888
- Conexant Cx20468 - with a modem
- Cirrus Logic CrystalWare 4236, CrystalClear SoundFusion CS4297, CS4299
- Crystal Semiconductors CS4205, CS4202
- C-Media CMI9738, 9739, 9761, 9880
- ESS ES1988 (with a modem)
- Empia EMP202 (2 channel, 20-bit DAC and 20-bit ADC, full duplex AC'97 2.2 compatible stereo audio CODEC)
- Intersil HMP9701 (obsolete, 48 kHz fixed samplerate)
- National Semiconductor LM4550, LM49321, LM49350, LM49352
- Philips UCB 1400 (with touchscreen controller)
- Realtek ALC5610 ALC5611[3][4][5]
- SigmaTel (now IDT) C-Major STAC 9460 (D/A only), 9461, 9462, 9463, 9200, 9202, 9250, 9251, 9220, 9221, 9223, 9750
- Silicon Image Si3024 (mono only)
- TriTech Microelectronics TR28022, 28026
- Yamaha YMF 743, 752, 753
- VIA VT1612, VT1616 (VIA Six-TRAC Vinyl Audio), VT82C686
- Winbond W83971
- Wolfson Microelectronics WM9701, WM9703, WM9704, WM9705 (w/touchscreen), WM9707, WM9708, WM9709 (DAC only), WM9711, WM9712 (w/touchscreen), WM9713 (w/touchscreen), WM9714
Front panel connector[edit]
Computer motherboards often provide a connector to bring microphone and headphone signals to the computer's front panel with standard color jack. Intel provides a specification for that header; the signal assignments are different for AC'97 and Intel High Definition Audioheaders.[6]
Operating system support[edit]
AC'97 is supported by most operating systems, such as Windows and Linux. Under DOS, applications access the sound hardware directly instead of through the operating system, and most DOS applications do not support AC'97. 64-bit versions of Windows 7 and later require a third-party driver for AC'97 support.[7]
See also[edit]
| Wikimedia Commons has media related to AC'97. |
What Is Ac97 Front Panel
- I²S (Integrated Interchip Sound)
References[edit]
Host controller[edit]
Like AC'97, HD Audio is a specification that defines the architecture, link frame format, and programming interfaces used by the controller on the PCI bus and by the codec on the other side of the link. Implementations of the host controller are available from at least Intel, Nvidia, and AMD.[7] Codecs which can be used with such controllers are available from many companies, including Realtek,[8]Conexant (including products of acquired Analog Devices' SoundMAX division),[9] Tempo Semiconductor, VIA, Wolfson Microelectronics, and formerly C-Media. Realtek currently supplies most of HD Audio codec chips used on motherboards and standalone cards.
Nearly all chipsets for x86 processors and x86 SoCs, designed for consumer and embedded PC markets, introduced since 2005, implements integrated HD Audio controller. The most recent exemption in consumer chipset market is AMD TRX40 (launched 2019), which, for first time since the early 2000s, does not itself integrate any kind of audio controller. Instead, motherboard manufacturers places USB audio controller chip, in pair with usual HD Audio codec chip, to provide onboard audio functionality. The Realtek ALC4050H controller and ALC1220 codec is the most common pair used in sTRX4 motherboards.
Front panel connector[edit]
Computer motherboards often provide a connector to bring microphone and headphone signals to the computer's front panel. Intel provides a specification for that header, but the signal assignments are different for AC'97 and HD Audio headers.[10]
The pin assignments for the AC'97 and HD Audio connectors are:[10]
| Pin | AC'97 | HD Audio (HDA) | ||
|---|---|---|---|---|
| Signal | Description | Signal | Description | |
| 1 | MIC |
| PORT 1L | Audio, left, port 1 |
| 2 | AUD_GND | Ground | GND | Ground |
| 3 | MIC BIAS |
| PORT 1R | Audio, right, port 1 |
| 4 | AUD_GND | Ground | PRESENCE# | HDA dongle/connector detection, active low |
| 5 | FP_OUT_R | Audio out, right, out (headphone-level capable), front panel | PORT 2R | Audio, right, port 2 |
| 6 | FP_RETURN_R | Audio, right, return (when jack is unconnected), front panel | SENSE1_RETURN | Port 1 jack detection |
| 7 | AUD_5V | Power, +5 V | SENSE_SEND | Jack detection sense, resistance multiplexed |
| 8 | KEY | Not present, physical key | KEY | Not present, physical key |
| 9 | FP_OUT_L | Audio, left, out (headphone-level capable), front panel | PORT 2L | Audio, left, port 2 |
| 10 | FP_RETURN_L | Audio, left, return (when jack is unconnected), front panel | SENSE2_RETURN | Port 2 jack detection |
The HDA 3.5 mm subminiature audio connectors differ from connectors used in the AC'97 specification and general audio equipment. A regular 3.5 mm audio jack (which is used in AC'97) typically has 5 pins: one pin for ground, two pins for stereo signal and two pins for return signal.[11] When there is no plug in the jack, the two stereo signals are connected to their return pins. When a plug is inserted, the stereo signals contact the respective channels on the plug and are disconnected from the jack's return pins. The HDA 3.5 mm jack does not have the two return audio signals; instead it has an isolated switch that senses the presence of a plug in the jack.[12]
In the AC'97 design, the audio output is always sent to the jack. If the headphones are not plugged in, the jack directs the audio to the return pins that are connected to the speakers. When a headphone is plugged into the front panel jack, the audio signal goes to the headphones; the return pins are disconnected, so no audio signal goes to the speakers. For the microphone jack, the return signal pins ground the microphone input when the microphone is not plugged in. Wwe smackdown vs raw 2009 pc game download rar. Many motherboards with AC'97 audio need two jumpers to short the pins in case no front panel audio module is connected, so audio passes to the speakers.[13]
In the HDA design, when the plug is not inserted, the codec sends the audio directly to the speakers (the audio does not go out to the front panel and then loop back to the speakers). When the plug is inserted, the isolated switch inside the jack informs the motherboard, and the codec sends audio to the headphones. A similar isolated switch is used to detect when a microphone has been plugged in.
HD Audio can sense the presence of an audio dongle.[14] A 10 kΩ pull-up resistor is attached to pin 4 (PRESENCE#). When the HDA dongle is plugged in, it pulls pin 4 to ground with a 1 kΩ resistor. The motherboard can determine if the dongle is plugged in by examining the logic level on pin 4. If the motherboard does not detect the presence of an HDA dongle, then it should ignore SENSE1_RETURN (pin 6) and SENSE2_RETURN (pin 10) signals. In AC'97, pins 2 and 4 are audio ground, but pin 4 is often disconnected. Consequently, an HDA motherboard would not detect the presence of an AC'97 dongle with a disconnected pin 4.
Intel warns that HDA dongles should be used with HDA motherboards:[15]
It is strongly recommended that motherboard designers only use Intel HD Audio analog front panel dongles with the Intel HD Audio analog front panel header to insure that the jack detection and dynamic re-tasking capability is preserved. Passive AC'97 analog front panel dongles (ones which leave the 5V Analog pin-7 line unconnected on the dongle) may be used with the Intel HD Audio analog front panel header. But note that the front panel jack detection and re-tasking functionality will be lost as the AC'97 jacks cannot support connection to the SENSE line. In addition, software must be aware that an AC'97 dongle is being used with an Intel HD Audio analog header since the software might need to dedicate codec ports that are connected to the header to meet the product's intended functionality.
The different signal assignments can cause trouble when AC'97 front-panel dongles are used with HDA motherboards and vice versa. An AC'97 dongle returns audio on pins 6 and 10 rather than a digital plug sensing signals. Consequently, a loud audio passage may make the HDA motherboard with AC'97 dongle believe that headphones and microphones are being plugged and unplugged hundreds of times per second. An AC'97 motherboard with an HDA dongle will route the AC'97 5 V audio supply (pin 7; silence) to the speakers instead of the desired left and right audio signals.
To avoid this, some motherboards allow choosing between HDA and AC'97 front panels in the BIOS. Even though the actual audio hardware is HD Audio, it will allow using the AC'97 front panel that way. Likewise, some modern enclosures have both an 'AC'97' and an 'HDA' plug at the end of the front-panel audio cable.
See also[edit]
References[edit]
- ^Smith, Tony (16 April 2004). 'Intel completes hi-def audio spec'. The Register. Situation Publishing Limited. Retrieved 14 January 2014.
- ^'High Definition Audio Specification 1.0a'(PDF). Intel Corporation. 2010. p. 17.
- ^Microsoft Knowledge Base Article 888111
- ^OpenSolaris Boomer Project Page, 2009
- ^snd_hda. Man.freebsd.org (2012-01-25). Retrieved on 2013-07-28.
- ^Manual Pages: azalia. OpenBSD.org (2012-03-15). Retrieved on 2018-02-03.
- ^AMD SB600 Product Information Page, 2009
- ^ALC888 Product Page, 2009
- ^Conexant - PC HD-AudioArchived 2013-08-19 at the Wayback Machine
- ^ abIntel Corporation (February 2005), Front Panel I/O Connectivity Design Guide(PDF), Version 1.3, pp. 19–25, archived from the original(PDF) on 2011-05-11, retrieved 2011-11-04
- ^Intel Corporation 2005, p. 20
- ^Intel Corporation 2005, p. 25
- ^Intel Corporation 2005, p. 21
- ^Intel Corporation 2005, p. 24
- ^Intel Corporation 2005, p. 19
External links[edit]
- High Definition Audio Specification 1.0a (June 17, 2010)
AC'97 (Audio Codec '97; also MC'97 for Modem Codec '97) is an audiocodec standard developed by Intel Architecture Labs in 1997. The standard was used in motherboards, modems, and sound cards.
The specification covers two types of component, and the 'AC-link' digital interface between them:
- an AC'97 digital controller (DC97), which is built into the southbridge of the chipset, and
- an AC'97 audio and modem codec, available from several vendors, which contains the analog components of the architecture.
AC'97 defines a high-quality, 16- or 20-bit audio architecture with 5.1 surround sound support for the PC. AC'97 supports a 96 kHz sampling rate at 20-bit stereo resolution and a 48 kHz sampling rate at 20-bit stereo resolution for multichannel recording and playback.
Integrated audio is implemented with the AC'97 Codec on the motherboard, a Communications and Networking Riser card, or an audio/modem riser card.
In 2004, Intel released Intel High Definition Audio (HD Audio) which is a successor that is not backward compatible with AC'97.[1] HD Audio has the capability to define up to 15 output channels, but in practice most motherboards provide no more than 8 channels (7.1 surround sound).
Revisions[edit]
AC'97 has had several revisions:[2]
- AC'97 1.x compliant indicates fixed 48K sampling rate operation (non-extended feature set)
- AC'97 2.1 compliant indicates extended audio feature set (optional variable rate, multichannel, etc.)
- AC'97 2.2 compliant indicates extended audio, enhanced riser audio support, and optional Sony/Philips Digital Interface Format
- AC'97 2.3 compliant indicates extended configuration information and optional jack sensing support
AC'97 revision 2.3 enables Plug and Play for the end user. This revision provides means for the audio codec to supply parametric data about its analog interface much like Intel High Definition Audio.
AC-Link[edit]
The AC-Link is a digital link that connects the DC97 (the controller) with the audio 'codecs.' It is composed of five wires: the 12.288 MHz clock, a 48 kHz sync signal, a reset signal, and two data wires which carry the actual audio data: sdata_out and sdata_in. The first four are outputs from the controller, while sdata_in carries input from the codec. The link carries a bidirectional serial data stream at a fixed bitrate (12.288 Mbit/s) between the controller and one or more codecs.
Front Panel Audio Header
Each 12.288 Mbit/s stream is divided into 256-bit frames (frame frequency is 48 kHz). This is therefore a time-division multiplexing scheme.
Every frame is subdivided in 13 slots. The first (slot 0) is 16 bits long and contains validity flags for the remaining slots, while the remaining 240 bits are divided in twelve 20-bit slots (slots 1–12), used as data slots.
Slots 1, 2 and 12 are used for non-audio data, while slots 3–11 carry up to nine channels of raw pulse-code modulation audio signals. Normally, six channels are used for 5.1 surround sound, and three channels are available for modem use. However, slots can be combined to provide a 96 kHz sampling rate for the L, R and C channels.
Lower sample rates (such as 44.1 kHz) are implemented using a handshake protocol between the controller and codec which skips data during certain frames. (This capability depends on the codec. Mafia 2 free download. Alternatively, sample rate conversion could be performed in the DC97 (controller) or in the software driver.)
Codec chips[edit]
Codec chips have an AC'97 interface on one side and analog audio interface on the other. They are usually small square chips with 48 pins (48-pin QFP package). They are D/A and A/D or only D/A.
- Analog Devices AD1819B, 1881A, 1885, 1886, 1887, 1980, 1981, 1985
- AKM (Asahi Kasei Microsystems) AK 4540, 4543, 4544A, 4545
- Avance Logic (now Realtek) ALC201A, ALC202/A, ALC650, ALC655, ALC658, ALC101, ALC202A, ALC250, ALC850, ALC888
- Conexant Cx20468 - with a modem
- Cirrus Logic CrystalWare 4236, CrystalClear SoundFusion CS4297, CS4299
- Crystal Semiconductors CS4205, CS4202
- C-Media CMI9738, 9739, 9761, 9880
- ESS ES1988 (with a modem)
- Empia EMP202 (2 channel, 20-bit DAC and 20-bit ADC, full duplex AC'97 2.2 compatible stereo audio CODEC)
- Intersil HMP9701 (obsolete, 48 kHz fixed samplerate)
- National Semiconductor LM4550, LM49321, LM49350, LM49352
- Philips UCB 1400 (with touchscreen controller)
- Realtek ALC5610 ALC5611[3][4][5]
- SigmaTel (now IDT) C-Major STAC 9460 (D/A only), 9461, 9462, 9463, 9200, 9202, 9250, 9251, 9220, 9221, 9223, 9750
- Silicon Image Si3024 (mono only)
- TriTech Microelectronics TR28022, 28026
- Yamaha YMF 743, 752, 753
- VIA VT1612, VT1616 (VIA Six-TRAC Vinyl Audio), VT82C686
- Winbond W83971
- Wolfson Microelectronics WM9701, WM9703, WM9704, WM9705 (w/touchscreen), WM9707, WM9708, WM9709 (DAC only), WM9711, WM9712 (w/touchscreen), WM9713 (w/touchscreen), WM9714
Front panel connector[edit]
Computer motherboards often provide a connector to bring microphone and headphone signals to the computer's front panel with standard color jack. Intel provides a specification for that header; the signal assignments are different for AC'97 and Intel High Definition Audioheaders.[6]
Operating system support[edit]
AC'97 is supported by most operating systems, such as Windows and Linux. Under DOS, applications access the sound hardware directly instead of through the operating system, and most DOS applications do not support AC'97. 64-bit versions of Windows 7 and later require a third-party driver for AC'97 support.[7]
See also[edit]
| Wikimedia Commons has media related to AC'97. |
What Is Ac97 Front Panel
- I²S (Integrated Interchip Sound)
References[edit]
- ^'1.2.1 AC'97 Compatibility'(PDF), High Definition Audio Specification, Revision 1.0a, Intel Corporation, 2010, p. 17
- ^Audio Codec '97(PDF), Revision 2.3 Rev 1.0 [sic], Intel Corporation, April 2002CS1 maint: extra punctuation (link)
- ^AC'97 InterfaceArchived March 2, 2012, at the Wayback Machine
- ^ALC5610 datasheet V1.4[permanent dead link]
- ^ALC5611 datasheet v1.3[permanent dead link]
- ^Intel Corporation (February 2005), Front Panel I/O Connectivity Design Guide(PDF), Version 1.3, pp. 19–25, archived from the original(PDF) on 2011-05-11, retrieved 2008-02-06
- ^VirtualBox Bug #5332, Oracle Corporation, 2009
Ac97 Front Panel Vs Hd Audio Front Panel
