Adjust Virtual COM example code to NOT use DTE (MCUXpresso SDK)

arno1 — Wed, 16 Jan 2019 16:17:46 GMT

I'm working on implementing USB CDC ACM (virtual com port) and MSC (mass storage) in a LPC54606 project, based on the LPCXpresso54608 example (lpc54608_dev_composite_cdc_msc_bm).

I don't want to use flow control (DTE), because the (already existing) application we are communicating with does not have this implemented.
Can someone point me in the right direction on how I should adjust the USB_DeviceCdcVcomCallback in virtual_com.c ?
I reckon I should change something in the kUSB_DeviceCdcEventSetControlLineState case, but it is not very clear to me what this does exactly.

Re: Adjust Virtual COM example code to NOT use DTE (MCUXpresso SDK)

FelipeGarcia — Thu, 24 Jan 2019 20:28:41 GMT

Hi Arno,

According to the USB spec you can change whether DTE is present or not in the the Control Signal Bitmap Values.

You are correct in your affirmation that flow control needs to be change in USB_DeviceCdcEventSetControlLineState.

Please see below the brief extracted from the spec.

In the following snippet is shown the lower byte of the uartBitmap. Here you should set them to 0.

I hope this helps.

Best regards,

Felipe

MCUXpresso General中的主题 Adjust Virtual COM example code to NOT use DTE (MCUXpresso SDK)

Adjust Virtual COM example code to NOT use DTE (MCUXpresso SDK)

Re: Adjust Virtual COM example code to NOT use DTE (MCUXpresso SDK)