LPC Microcontrollers中的主题 USB CDC Problem 4096 bytes https://community.nxp.com/t5/LPC-Microcontrollers/USB-CDC-Problem-4096-bytes/m-p/524627#M7263 <HTML><HEAD></HEAD><BODY><STRONG>Content originally posted in LPCWare by mb1391 on Tue Feb 11 01:46:25 MST 2014</STRONG><BR /><SPAN>Hi,</SPAN><BR /><BR /><SPAN>I am using nxpUSBlib v0.98b and LPCExpresso v6.1.0 for USB Virtual com port implementation on LPC17xx-40xx.</SPAN><BR /><BR /><SPAN>I have a problem sending data from target hardware to a Windows PC, while PC to target hardware is working fine.</SPAN><BR /><BR /><SPAN>When I send bytes from target hardware to PC, I am supposed to see the data at PC end immediately. But the data gets stuck somewhere and when I keep sending the data, all of a sudden I get 4096 bytes of the stuck data on PC. So I have to wait for data until 4096 bytes are sent.</SPAN><BR /><BR /><SPAN>As far as I know, the usbser.sys requests 4096 bytes at a time by default, but data of lesser size is allowed to be sent over the virtual com port.</SPAN><BR /><BR /><SPAN>What could be the possible issue here?</SPAN><BR /></BODY></HTML> Wed, 15 Jun 2016 16:49:32 GMT lpcware 2016-06-15T16:49:32Z USB CDC Problem 4096 bytes https://community.nxp.com/t5/LPC-Microcontrollers/USB-CDC-Problem-4096-bytes/m-p/524627#M7263 <HTML><HEAD></HEAD><BODY><STRONG>Content originally posted in LPCWare by mb1391 on Tue Feb 11 01:46:25 MST 2014</STRONG><BR /><SPAN>Hi,</SPAN><BR /><BR /><SPAN>I am using nxpUSBlib v0.98b and LPCExpresso v6.1.0 for USB Virtual com port implementation on LPC17xx-40xx.</SPAN><BR /><BR /><SPAN>I have a problem sending data from target hardware to a Windows PC, while PC to target hardware is working fine.</SPAN><BR /><BR /><SPAN>When I send bytes from target hardware to PC, I am supposed to see the data at PC end immediately. But the data gets stuck somewhere and when I keep sending the data, all of a sudden I get 4096 bytes of the stuck data on PC. So I have to wait for data until 4096 bytes are sent.</SPAN><BR /><BR /><SPAN>As far as I know, the usbser.sys requests 4096 bytes at a time by default, but data of lesser size is allowed to be sent over the virtual com port.</SPAN><BR /><BR /><SPAN>What could be the possible issue here?</SPAN><BR /></BODY></HTML> Wed, 15 Jun 2016 16:49:32 GMT https://community.nxp.com/t5/LPC-Microcontrollers/USB-CDC-Problem-4096-bytes/m-p/524627#M7263 lpcware 2016-06-15T16:49:32Z