WM8350GEB/V Wolfson Microelectronics, WM8350GEB/V Datasheet - Page 114

• Manufacturer Part Number: WM8350GEB/V
• Description: Audio CODECs Audio CODEC plus pwr management
• Manufacturer: Wolfson Microelectronics

Specifications of WM8350GEB/V

• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

WM8350
14.4 DEVELOPMENT MODE
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The WM8350 can start in different modes depending on the state of the CONF1 and CONF0 pins.
Development mode is selected by tying CONF1 and CONF0 to logic 0.
Development mode gives complete control over the configuration and startup behaviour of the
WM8350 and allows overriding the default values of selected registers (listed in Table 63). It enables
configuration of the WM8350 before startup. This is especially useful for evaluation and debugging.
In low-volume production, an external ‘genie’ (low-cost, small-size microcontroller) may be used to
configure the WM8350 in Development mode. The ‘genie’ is used to write the required register
values to generate the desired supplies and to configure the GPIO pins as required. These register
write operations can be achieved via a secondary control interface, which is provided by redirecting
the control interface to two GPIO pins as described below.
The configuration mode pins CONF1 and CONF0 should be tied to fixed logic levels. The start-up
sequence that they control is initiated on every transition from the OFF to the ACTIVE state.
14.4.1
In Development mode, the 2-wire control interface is initially redirected from the primary control
interface (dedicated SDATA and SCLK pins, which require a DBVDD supply) to the secondary
control interface (the GPIO10 and GPIO11 pins, which can run on an externally generated supply
provided through the LINE pin). When using GPIO pins for the Control Interface, GPIO11 provides
the SDATA functionality, and GPIO10 provides the SCLK functionality.
Use of the secondary interface makes it possible to configure the WM8350 before the DBVDD supply
voltage becomes available (e.g. in the OFF and PRE-ACTIVE states). The control interface can be
switched back to the primary interface at any time by writing to the USE_DEV_PINS bit. In a typical
application, the primary control interface would be selected after the WM8350 is fully configured.
The device address for the secondary control interface is 0x34h, and cannot be changed. In
development mode only, the primary interface address can be selected by writing to the DEV_ADDR
bits through the secondary interface. Note that this functionality is only available in Development
mode.
Table 61 Control Interface Switching in Development Mode
R6 (06h)
Interface
Control
Note: In custom modes (CONF[1:0]≠00), the secondary control interface is never used and the
control bits described here have no effect.
ADDRESS
CONTROL INTERFACE REDIRECTION
14:13
BIT
15
USE_DEV_P
INS
DEV_ADDR
[1:0]
LABEL
DEFAULT
00
1
Selects which pins to use for the 2-wire
control:
0 = Use 2-wire I/F pins as 2-wire interface
1 = Use GPIO 10 and 11 as 2-wire interface,
e.g. to download settings from PIC.
Only applies when CONFIG pins[1:0] = 00.
Selects device address (only valid when
CONF_STS = 00)
00 = 0x34
01 = 0x36
10 = 0x3C
11 = 0x3E
DESCRIPTION
PD, March 2010, Rev 4.2
Production Data
114