AU335 Theory of Operation

this section describes how specific components operate on the au335, and which audio formats are supported on board leds (pwr) the au335 has a single red led to indicate that the power is on the led will flash during the firmware update process it will also flash a certain number of times to indicate an error state the flash codes are described below flash code description 2 unspecified error 3 network recovery script is preparing to run on a device configured for network recovery 4 no upgrade file found 5 failed to load kernel module 6 board is not capable of running the current firmware version 7 a piece of onboard hardware is not working correctly 8 problem related to the storage device (either the usb drive or microsd card) 9 problem related to the registry/nand 10 the autorun script encountered a load/run error 12 unable to find a bootable image service button the service (svc) button can be used for a number of debugging tasks when it is pressed, a gpio pin is pulled low, and when it is released it normally sets the gpio pin to be pulled high reset button the reset button is connected to the reset circuit pressing the reset button will send an initial signal to the system software, and holding the reset button low for approximately four seconds will cause a hard reset microsd slot the au335 have one microsd slot, which supports transfer modes up to uhs 1 ddr50 (50mb/s) there is no inherent limit on the storage capacity of microsd cards used with the player