
Controls and Indicators Interface
28 Module Hardware Description May 31, 2008
Controls and Indicators InterfaceThe W24 incorporates several interface signals for controlling and monitoring the module's
operation. The following paragraphs describes these signals and their operation.
Table2-12 gives a description of the controls and indicators signals.
Reset
The RESET_N output signal indicates the W24's operating status. This signal is set high after
power up, when W24 is operating. It is set low when W24 is powered off.
When the RESET_N signal is low, the W24 interface signals are disabled and do not represent
any valid data or state. Furthermore, any input signals connected to the W24 interface must be
disabled (tri-state) or set low when RESET_N is low.
VREF Reference Regulator
The W24 incorporates a regulated voltage output, VREF. The regulator provides a 2.8V output
for use by the customer application. This regulator can source up to 100 mA of current to power
any external digital circuits. VREF voltage is present whenever the W24 is powered up,
regardless of it's mode of operation.
Table 2-12:Controls and Indicators
Pin # Pin Name Description
25 RESET_N W24 system readiness output
indicator. When high, W24 is
operating.
27 VREF 2.75V regulated output.
Supplies up to 100mA to the
external circuits.
26 WKUPO_N Host application wake-up signal
indicator.
16 WKUPI_N Device application wake-up sig-
nal control.
41 ANT_DET Antenna physical connection
detect indicator.
39 TXEN_N Transmission burst indication.
49 GPRS GPRS/EGPRS coverage indica-
tor.
60 WIFI_LED_LCD_RS Wi-Fi Activity LED indicator.
45 MSEL_UID Mode Select.