LPC MicrocontrollersのトピックRe: RTOS integration issues

RTOS integration issues

lpcware — Wed, 15 Jun 2016 16:52:13 GMT

Content originally posted in LPCWare by rocketdawg on Thu Aug 23 12:37:19 MST 2012
I have nxpUSBLib working on a LPCExpresso LPC1769. I modified the generic HID example for my VID/PID and descriptors.
The device enumerates using this framework
I want to use an RTOS and I have a thread that replaces the for(;;) loop. This thread runs every 10ms and it is running.

The issue is that the device does not work at all. The USB reset causes the Host to send GetDescriptor but the stack does not ACK

I am seeing an interrupt upon connection, but the device just does not send anything.
So I an wondering what could be the difference between the standard CMSIS startup and the one provide by FreeRTOS?

Re: RTOS integration issues

lpcware — Wed, 15 Jun 2016 16:52:13 GMT

Content originally posted in LPCWare by rocketdawg on Fri Aug 24 10:41:57 MST 2012
interesting update.
The doc says that the the calls
USB_Device_USBTask(...)
USB_USBTask()

can be called every 30ms. Doesn't seem to be the case.
I was calling every 10ms but the device fails to enumerate. I change to 5ms and found that it gets farther into the enumeration
changed it to 1ms and it enumerates fine.

All the provided code examples user a super loop so I am wondring if this should be explained in the doc if someone wants to use a RTOS.

Since my device enumerates with 10ms polling rate, I can set the wait time to 1ms for enumeration, and then back it off to 10ms for normal operation.