WM9093ECSSLASHR datasheet(43/84 Pages) WOLFSON

43 / 84 page

Production Data

WM9093

PD, March 2012, Rev 4.2

Note that a ‘Dummy’ write can be inserted into a control sequence by commanding the sequencer to

write a value of 0 to bit 0 of Register R255 (FFh). This is effectively a write to a non-existent register

location. This can be used in order to create placeholders ready for easy adaptation of the sequence.

For example, a sequence could be defined to power-up a mono signal path from IN1+ and IN1- to

headphone, with a ‘dummy’ write included to leave space for easy modification to a stereo signal path

configuration. Dummy writes can also be used in order to implement additional time delays between

In summary, the Control Register to be written is set by the WSEQ_ADDR field. The data bits that are

written are determined by a combination of WSEQ_DATA_START, WSEQ_DATA_WIDTH and

WSEQ_DATA. This is illustrated below for an example case of writing to the VMID_RES field within

In this example, the Start Position is bit 01 (WSEQ_DATA_START = 0001b) and the Data width is 2

bits (WSEQ_DATA_WIDTH = 0001b). With these settings, the Control Write Sequencer would update

the Control Register R1 [2:1] with the contents of WSEQ_DATA [1:0].

Figure 14 Control Write Sequencer Example

DEFAULT SEQUENCES

When the WM9093 is powered up, a number of Control Write Sequences are available through

default settings in both RAM and ROM memory locations. The pre-programmed default settings

comprise a Headphone Start-Up and a Generic Shut-Down sequence.

Note that the start-up sequence does not include audio signal path or gain setting configuration; this

must be implemented prior to scheduling the sequence. Also, the start-up sequence does not include

configuration of the master bias. The user must enable the clock and the master bias by setting

OSC_ENA and VMID_ENA prior to executing the start-up control sequence. These registers may be

reset to 0 after executing the shut-down sequence.

Index addresses 0 to 15 may be programmed to users’ own settings at any time, as described in

“Programming a Sequence”. Users’ own settings remain in memory regardless of WSEQ_ENA, and

are not affected by software resets (i.e. writing to Register R0). However, any non-default sequences

are lost when the device is powered down.

WM9093ECS/R Datasheet(PDF) 43 Page - Wolfson Microelectronics plc