Specifications

ESS Technology, Inc. SAM0025A-062397 73
ES1879 DATA SHEET
REGISTERS
PRELIMINARY
Master Volume Control (64h, R/W)
Bits Definitions:
Opamp Calibration Control (65h, R/W)
In the analog circuitry of the ES1879, operational
amplifiers that require calibration go through a calibration
procedure that takes about 200 msec to perform. During
this period, the analog outputs of the chip (AOUT_L,
AOUT_R, and FDXO) are muted.
The calibration procedure occurs automatically after
hardware reset and can be started at any time thereafter
by writing 01h to mixer register 65h.
Bits Definitions:
Hardware Volume Interrupt Request Reset (66h, W)
Any write to this register resets the hardware volume
interrupt request. This register is write-only.
Split
mode
enable
MPU-401
IRQ mask
Volume
count
HWV
IRQ flag
HWV opera-
tion mode
HWV
interrupt
mask
SB Pro
master
volume
disable
76543210
Bits Name Description
7Split
mode
enable
1 = Enable Split mode for hardware volume
control. This mode splits hardware volume
counters (61h and 63h) from the master vol-
ume control registers (60h and 62h). The host
software is responsible for reading the
counter register and updating the master vol-
ume registers.
0 = Disable Split mode. Hardware volume and
master volume registers are slaved together.
Registers 61h and 63h cannot be indepen-
dently accessed.
6 MPU-401
IRQ mask
This bit is AND’d with the MPU-401 interrupt
request. If this bit is low, the MPU-401 inter-
rupt request stays low. This bit is cleared by
hardware reset.
5 Volume
count
1 = Count up and down by 3 for each push of
UP or DOWN button.
0 = Count up and down by 1 for each push of
UP or DOWN button.
This bit is cleared by hardware reset.
4 HWV IRQ
flag
Read-only interrupt request from hardware
volume event.
3:2 HWV
operation
mode
Selects hardware volume operation
mode:
bit 3 bit 2 mode
0 0 Normal 3-wire mode (hard-
ware reset default).
0 1 2-wire mode: UP and DOWN
inputs low together act as a
MUTE input low.
1 0 2-wire enabled, debounce
reduced (40 msec to 10
µsecs), auto-increment/-decre-
ment disabled.
1 1 Hardware volume control dis-
abled.
1HWV inter-
rupt mask
This bit is AND’d with the hardware volume
interrupt request before being OR’d with the
audio 1 interrupt request. If this bit is low, the
hardware volume interrupt request does not
get OR’d with the audio 1 interrupt request.
This bit is cleared by hardware reset. When
high, enables the hardware volume control to
be shared with the audio interrupt.
0 SB Pro
master
volume
disable
When low, a write to legacy master volume
registers 22h or 32h is translated into a write
to the hardware master volume counters,
Mixer registers 60h and 62h. If high, the SB
Pro Master Volume registers are, in effect,
read-only. This bit is cleared by hardware
reset.
0 Opamp calibration
7654321 0
Bits Name Description
7:1 – Reserved. Always write 0.
0Opamp
calibra-
tion
Read:
1 = Opamp calibration in progress. Opamp cal-
ibration occurs if a one is written to this bit after
a hardware reset. Calibration can take up to
200 msec, during which the analog outputs
(AOUTL/AOUTR and FDXO) of the ES1879
are muted.
Write:
1 = Start opamp calibration.
0 = Stop opamp calibration immediately. This
is not recommended.
Write: Reset hardware volume interrupt request
76543210
Bits Name Description