AD1986 Datasheet, PDF (46/52 Pages) Analog Devices – AC ’97 SoundMAX CODEC

AD1986
Preliminary Technical Data
SENSE REGISTER (REGISTER 0x6A, PAGE 01)
This address represents multiple registers (one for each supported function code (FC [3:0] bits (0x66 D [04:01])). The ST [2:0] bits are
only reset by power-on. They are used by the BIOS to store configuration information (per AC ’97 Revision 2.3 specifications) and must
not be reset by soft, hard or hardware resets. The remaining bits are the result of the last sense operation performed by the impedance
sensing circuitry.
Reg Name
0x6A1 Sense
Register
D15 D14 D13 D12 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0 Default
ST2 ST1 ST0 S4 S3 S2 S1 S0 OR1 OR0 SR5 SR4 SR3 SR2 SR1 SR0 0xxxxx
Table 72.
Register
SR [5:0] (RO)
(Sense Result
Bits, RO)
OR [1:0] (RO)
(Order Bits)
S [4:0] (RO)
S [4:0] (RO)
Function
These bits are used to report a vendor specific fingerprint or value. (resistance, impedance, reactance,
etc. Used with the OR bits which are the multiplying factor.
Default
Default: 0
These bits indicate the order the sense result bits SR [5:0] are using. For example, if measuring resistance SR = 1/OR =
11: the result is 1 KΩ.
OR [1:0]
Order Value
00
10⁰—SR bits indicate the actual impedance in ohms
Default
01
10¹â€”SSR bits indicate the impedance in ohms × 10
10
10²â€”SR bits indicate the impedance in ohms × 100
11
10³â€”SSR bits indicate the impedance in ohms × 1,000
Sensed bits meaning relates to the I/O being sensed as input or output. Read only. Sensed bits (when output sense
cycle initiated). This field allows for the reporting of the type of output peripheral/device plugged in the jack. Values
specified below should be interrogated with the SR [5:0] and OR [1:0] for accurate reporting.
S [4:0]
Sense Value
0x00
Data not valid. Indicates that the reported value(s) is invalid
0x01
No connection. Indicates that there are no connected devices
Default
0x02
Indicates a specific fingerprint value for devices that are not specified or are
unknown
0x03
Speakers (8 Ω)
0x04
Speakers (4 Ω)
0x05
Powered speakers
0x06
Stereo headphone
0x07
SPDIF out (electrical)
0x08
SPDIF out (TOS)
0x09
Mono headset (mono speaker left channel and mic. Read Functions 5 and 6 for
matching microphone)
0x0A
Allows a vendor to report sensing other type of devices/peripherals. SR [5:0]
together with OR [1:0] provide information regarding the type of device sensed
0x0B–0x0E
Reserved
0x0F
Unknown (use fingerprint)
0x10–0x1F
Reserved
Sensed bits (when input sense cycle initiated). This field allows for the reporting of the type of input peripheral/device
plugged in the jack. Values specified below should be interrogated with the SR [5:0] and OR [1:0] bits for accurate
reporting.
ST [2:0]
Sense Value
0x10
Data not valid. Indicates that the reported value(s) is invalid
0x11
No connection. Indicates that there are no connected devices
Default
0x12
Indicates a specific fingerprint value for devices that are not specified or are
unknown
0x13
Microphone (mono)
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