Serial Port; Audio Outputs; On-Board Leds - BrightSign 4K Series Hardware Manual

from the NAND flash device into the SDRAM and then execute the code from the SDRAM. The SDRAM runs at a clock
rate of 1067MHz, with a data rate of 2133MT/s.

Serial Port

The 4K1042 and 4K1142 have a built-in UART that communicates with the RS-232 level shifter. The MAX232 creates
valid RS-232 voltage levels for the transmit pin by using a capacitive voltage switcher.

Audio Outputs

BrightSign 4K players each have a single high quality audio DAC device, which takes in digital audio signals from the
CPU in an I2S audio format. The AUD_LRCIN is the framing signal for the audio and runs at the frame rate of the audio
source (usually either 44.1KHz or 48KHz). The AUD_BITCLK signal is typically 32 times higher than the AUD_LRCIN.
The audio output is fed through an amplifier and sent directly to the audio output jack. It can drive a 32Ω load with a 2V
RMS signal.

On-Board LEDs

There are eight on-board LEDs that indicate the following:
LED
Green power (Pwr)
Green file-system activity
(Bsy)
Green MicroSD activity
(µSD)
Green network activity (Svr)
Green Ethernet activity (Eth)
Green WiFi activity
All information provided in this reference manual applies to products under development. The characteristics and specifications of these products are subject to
change without notice. BrightSign assumes no obligation regarding future manufacturing unless otherwise agreed to in writing. © BrightSign LLC, 2014
Displays when the board is powered up and not in reset mode.
Flashes any time there is file-system activity (on any storage device)
Displays when a MicroSD card is present.
Displays when the player is connected to the BrightSign Network.
Flashes when the player is connecting to the network. Displays when connected.
Flashes when the player is connecting to the wireless network. Displays when connected.
BrightSign 4K242, 4K1042, 4K1142
Indication
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