XS156 Theory of Operation

this section describes how specific components operate on the hd225 and hd1025 on board leds the four on board leds have the following indicators led indication green power ( pwr ) displays when the board is powered up and not in reset mode flashes during the firmware update process green file system activity ( bsy ) flashes any time there is file system activity (on any storage device) blue wifi ( wifi icon ) flashes when the board is being updated red status ( err ) flashes a certain number of times to indicate which error is occurring the flash codes are described below 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 on board 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 11 wifi related error 12 unable to find a bootable image on board switch / svc button the on board switch is connected to the gpio02, which is pulled low when the service (svc) button is pressed conversely, a pull up on the button normally sets the gpio02 to be pulled high reset switch / gpio button the on board switch is connected to the reset circuit pulling low on the reset button for less than 2 seconds will initiate an orderly system reset under software control at the rising edge of the signal if the reset button is pulled low for more than 6 seconds, an immediate hard reset is performed sdio slot the xs156 provides one sd card interface capable of uhs 1 operation at up to ddr50 transfer rates a +3 3v power supply is provided for the card this power supply can be switched on and off by the firmware, allowing it to power cycle the sd card wireless module the xs156 has an m 2 e key for wifi/bluetooth modules