https://community.nxp.com/t5/Processor-Expert-Software/How-to-know-if-USB-data-buffer-is-completely-transmitted/m-p/1728933#M5710 <P><BR />I am developing an application based on the LCP5526 microcontroller. From USB,configured as VCOM, I need to receive and transmit a large amount of data (size&gt;20kbyte). The size of the USB buffer is 64 bytes, so I would like to know:</P><P>- what happens if I receive a data amount greater than 64 bytes<BR />- to transmit data, I need to fragment my buffer (called BUFFER A) into multiple parts (called BUFFER B[0], B[1], B[2], ..., B[n]) and transmit them separately. How do I know that a buffer (B[i]) has been completely transmitted before moving on to the next (B[i+1])?</P><P>Has anyone of you had a similar problem? In that case, how was it solved? Thank you very much for your help and collaboration Best regards</P> Mon, 25 Sep 2023 12:46:57 GMT _Ferrari_ 2023-09-25T12:46:57Z https://community.nxp.com/t5/Processor-Expert-Software/How-to-know-if-USB-data-buffer-is-completely-transmitted/m-p/1728933#M5710 <P><BR />I am developing an application based on the LCP5526 microcontroller. From USB,configured as VCOM, I need to receive and transmit a large amount of data (size&gt;20kbyte). The size of the USB buffer is 64 bytes, so I would like to know:</P><P>- what happens if I receive a data amount greater than 64 bytes<BR />- to transmit data, I need to fragment my buffer (called BUFFER A) into multiple parts (called BUFFER B[0], B[1], B[2], ..., B[n]) and transmit them separately. How do I know that a buffer (B[i]) has been completely transmitted before moving on to the next (B[i+1])?</P><P>Has anyone of you had a similar problem? In that case, how was it solved? Thank you very much for your help and collaboration Best regards</P> Mon, 25 Sep 2023 12:46:57 GMT https://community.nxp.com/t5/Processor-Expert-Software/How-to-know-if-USB-data-buffer-is-completely-transmitted/m-p/1728933#M5710 _Ferrari_ 2023-09-25T12:46:57Z https://community.nxp.com/t5/Processor-Expert-Software/How-to-know-if-USB-data-buffer-is-completely-transmitted/m-p/1801219#M5770 <P>You can configure USB interrupt that routes to NVIC on LPC552x. Whenever you receive data in USB buffers, the handler gets called. You might find this helpful - <A href="https://github.com/nxp-mcuxpresso/mcux-sdk-middleware-usb/blob/main/docs/MCUXpresso%20SDK%20USB%20Stack%20Composite%20Host%20User's%20Guide.pdf" target="_blank">https://github.com/nxp-mcuxpresso/mcux-sdk-middleware-usb/blob/main/docs/MCUXpresso%20SDK%20USB%20Stack%20Composite%20Host%20User's%20Guide.pdf</A><BR /><BR />There are callbacks that can be configured which are called when you transmit or receive data on USB buffers.</P> Sat, 03 Feb 2024 19:21:12 GMT https://community.nxp.com/t5/Processor-Expert-Software/How-to-know-if-USB-data-buffer-is-completely-transmitted/m-p/1801219#M5770 gaurav_sharma 2024-02-03T19:21:12Z