BCM4330 Preliminary Data Sheet
GPIO Interface
GPIO Interface
There are seven general purpose I/O (GPIO) pins available on the WLAN section of the BCM4330 that can be
used to connect to various external devices.
Upon power up and reset, these pins become tri-stated. Subsequently, they can be programmed to be either
input or output pins via the GPIO control register. An internal pull-up resistor is included on each GPIO. If a GPIO
output enable is not asserted, and the corresponding GPIO signal is not being driven externally, the GPIO is
read as high.
External Coexistence Interface
An external handshake interface is available to enable signaling between the device and an external co-located
wireless device, such as GPS, WiMax, or UWB, to manage wireless medium sharing for optimum performance.
The following signals can be enabled by software on the indicated WL_GPIO pins:
• ERCX_STATUS—WL_GPIO1
• ERCX_FREQ—WL_GPIO2
• ERCX_RF_ACTIVE—WL_GPIO3
• ERCX_TXCONF—WL_GPIO4
• ERCX_PRISEL—WL_GPIO5
UART Interface
One UART interface can be enabled by software as an alternate function on pins WL_GPIO4 and WL_GPIO_3.
Provided primarily for debugging during development, this UART enables the BCM4330 to operate as RS-232
data termination equipment (DTE) for exchanging and managing data with other serial devices. It is compatible
with the industry standard 16550 UART, and it provides a FIFO size of 64 × 8 in each direction.
JTAG Interface
The BCM4330 supports the IEEE 1149.1 JTAG boundary scan standard for performing device package and PCB
assembly testing during manufacturing. In addition, the JTAG interface allows Broadcom to assist customers by
using proprietary debug and characterization test tools during board bringup. Therefore, it is highly
recommended to provide access to the JTAG pins by means of test points or a header on all PCB designs.
Caution! The BCM4330 I/O interface pins are not 3.3V tolerant. All I/O signaling should be limited to
2.9V ±3%, 2.5V, 1.8V, or 1.2V, depending on the I/O power supply voltage VDDIO. This applies to the
GPIO, External Coexistence, UART, and JTAG signals.
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BROADCOM
BCM4330 Preliminary Data Sheet
April 28, 2011 • 4330-DS304-RI
Page 73
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