topic Re: LPC1768 usb OTG + external hid keyboard - problem in LPC Microcontrollers

LPC1768 usb OTG + external hid keyboard - problem

olegle — Mon, 16 Jan 2017 12:35:17 GMT

Hello, Freinds!
The problem with enumerating HID keyboard on the LPC1768. I connect the keyboard to the USB LPC1768 host. I am using the code library from Keil. At power LCP1768 start working with the keyboard correctly. But if I extract the keyboard and connect keyboard again - its doesnt work. Maybe its impossible to hot connection of keyboard to MCU?
My code below:

void USBH_Thread (void const *arg) {
char con = 0; /* Connection status of keyboard */
char con_ex = 40; /* Previous connection status + initial time in 100 ms intervals for initial display */
uint8_t out[64]; /* Output to keyboard LEDs */
out[0]=1;
USBH_Initialize (0); /* Initialize USB Host 0 */

while (1) {
con = USBH_HID_GetDeviceStatus(0) == usbOK; /* Get kbd connection status */

   if ((con ^ con_ex) & 1) { /* If connection status changed */
   if (con) {
      USBH_HID_Write (0,(uint8_t *)&out,1);/* Turn on NUM LED */
      printf ("\nKeyboard connected\n");
   } else {
      printf ("\nKeyboard disconnected ...\n");
   }
   con_ex = con;
   } else if (con_ex > 1) {
   con_ex -= 2; /* Decrement initial time */
   if ((con_ex <= 1) && (!con)) {
      printf ("\nNo keyboard connected ... \n");
      con_ex = con;
   } else {
      osDelay(200);
   }
   }
   osDelay(100);
   }
}
osThreadDef(USBH_Thread, osPriorityNormal, 1, NULL);

Re: LPC1768 usb OTG + external hid keyboard - problem

Carlos_Mendoza — Wed, 18 Jan 2017 21:03:25 GMT

Hi Oleg Le,

I'm not familiar with the Keil Library, I would recommend you to contact the Keil Support team:

Keil Product Support

Hope it helps!

Best Regards,
Carlos Mendoza
Technical Support Engineer

Re: LPC1768 usb OTG + external hid keyboard - problem

olegle — Mon, 23 Jan 2017 08:40:48 GMT

Hi, Carlos!

Ok, thanks a lot, i'll ask Keil support!

>Четверг, 19 января 2017, 0:03 +03:00 от Carlos_Mendoza <admin@community.nxp.com>:

>NXP Community

>Re: LPC1768 usb OTG + external hid keyboard - problem

>reply from Carlos_Mendoza in LPC - View the full discussion

Re: LPC1768 usb OTG + external hid keyboard - problem

承王 — Fri, 08 Sep 2017 01:41:42 GMT

Hi：

I have the same problem with you. do you have solve this problem?

Re: LPC1768 usb OTG + external hid keyboard - problem

elavarasanselvaraj — Mon, 10 Jan 2022 18:41:01 GMT

hi,

i am using lpc1768 based custom board with hid keyboard application.

it works well normally. but not working when pc returns from sleep.

can someone help to fix this...is it problem with windows driver/settings? or can we fix at embedded side?

thanks in advance,

elavarasan.s