USB(0/1)_LEDN LED indicator not working

[janbertran]

Both pins work if configred as GPIO mode but not if configured as USB led indicators for their respective USB device controllers.

The indicator for USB1 never goes on (with USB1 configured), the USB0 led is always on in one board and blinks for a moment in another board when plugging/unplugging USB connector but is also always on.

Tested with different USB demos.

Microcontroller is a LPC54S018M

pins configured as

//Usb FS Led (M8)
IOCON->PIO[2][15] = IOCON_PIO_FUNC(IOCON_FUNC2) | IOCON_PIO_DIGIMODE(1);
//Usb HS Led (P10)
IOCON->PIO[2][17] = IOCON_PIO_FUNC(IOCON_FUNC2) | IOCON_PIO_DIGIMODE(1);

There is a post describing similar behavior on LPC18xx/LPC43xx

Thanks

Jan

[Sabina_Bruce · Accepted solution]

Hello Jan,

After checking with the design team, they have confirmed that these pins have an optional configuration for USB led indicators, but were not implemented in the LPC54018M. This is the reason why they are not responsive when configuring them as the USB LED indicators.

In this case you will need to manually set the leds using GPIO in order to detech when a USB device is connected or disconnected in your application.

Best Regards,

Sabina

[nxf51211]

Hi,

I'd like to ask you if you are using a NXP development board (and which one) or if you are trying the demos with a custom board that has the LPC54S018M microcontroller. Also, I would like to ask what SDK are you using and if you could provide me the link to the post describing the similar behavior on LPC18xx/LPC43xx.

Best Regards,

Ricardo Delsordo

[janbertran]

Hi,

Only tested with custom board, leds active low as in datasheet for example: P2_17 USB1_LEDN — USB1-configured LED indicator (active low).

I have not seen any led dedicated to USB activity connected on evaluation boards, so not simple to test on them.

The SDK is 2.5.0

Here is the link to message "USB dedicated LED outputs (LPC18xx/LPC43xx)"

https://community.nxp.com/message/749284

Best Regards

Jan

[nxf51211]

Hi,

Could you please provide me the schematics of your custom board, and also the SDK project you used (with your modifications) so I can check on my side what might be the issue?

Best Regards,

Ricardo Delsordo

[janbertran]

Now I have tried it with the eval-board and using a multimeter instead of led

Board is LPC54018M-EVK Rev1

SDK: 2.5

project: lpcxpresso54s018m_dev_cdc_vcom_bm

changes:

files:

- source/usb_device_config.h   --> go to hi-speed usb1 instead of full-speed usb0

/*! @brief LPC USB IP3511 FS instance count */
#define USB_DEVICE_CONFIG_LPCIP3511FS (0U)

/*! @brief LPC USB IP3511 HS instance count */
#define USB_DEVICE_CONFIG_LPCIP3511HS (1U)

- board/pin_mux.c

add this line into function "void BOARD_InitPins(void)"

    IOCON_PinMuxSet(IOCON, 2U, 17U, IOCON_DIGITAL_EN | IOCON_FUNC2 | IOCON_DIGITAL_EN);

[janbertran]

forgot to add:

mesure pin 20 in connector J13

Best regards