Texas Instruments Stellaris RDK-IDM-SBC, Руководство пользователя

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Hardware Description
18 November 28, 2011
I
2
S Audio
The IDM-SBC has advanced audio capabilities using an I2S-connected Wolfson WM8510
CODEC. The CODEC’s integrated amplifier can directly drive an 8
Ω
speaker. Although the
CODEC supports a microphone input, pin count limits on the LM3S9B92 result in this feature
being unconnected. The Microphone signals are still routed to connector J8 in-case the user
wishes to wire the ADCDAT signal to the LM3S9B92.
The Audio CODEC has a number of control registers which are configured using the I2C bus
signals. CODEC settings can only be written, but not read, using I2C. Refer to the StellarisWare®
example applications for programming information and to the WM8510 data sheet for complete
register details.
In the default configuration, the LM39B92 provides the master Bit Clock (BCLK) and System Clock
(MCLK) to the CODEC. Since the CODEC has only one set of clock I/Os for both audio-out and
audio-in functions, only the LM39B92 I
2
S module transmit clocks are connected.
DriverLib provides I
2
S source code, with most examples showing Audio Output.
Controller Area Network (CAN)
Controller Area Network (CAN) is a multicast, shared serial bus standard for connecting
automotive or industrial systems. The IDM-SBC board includes a CAN transceiver (U5) capable of
communicating at up to 1Mb/s. The end-points of the CAN bus should be properly terminated with
12
0? resistors.
Serial Flash and microSD Card
To supplement the LM3S9B92 microcontroller’s internal Flash memory, the IDM-SBC board
includes a 1MB on-board serial Flash memory and a microSD card slot. Both devices share a SPI
Table 2-2. I
2
S Audio-Related Signals
Microcontroller Pin Board Function
PB3/I2C0SDA CODEC Configuration Data
PB2/I2C0SCL CODEC Configuration Clock
PE5/I2STXSD Audio Out Serial Data
PE4/I2STXWS Audio Out Framing signal
PB6/I2STXSCK Audio Out Bit Clock
PF1/I2STXMCLK Audio Out System Clock
Table 2-3. CAN-Related Signals
Microcontroller Pin Board Function
PB5/CAN0TX CAN Transmit Data
PB4/CAN0RX CAN Receive Data