Posted on November 28, 2017 at 10:53Hello Community,
as written in my last post
https://community.st.com/message/175475-nucleo-h743zi-problems-setting-usb-fs-device-into-operation
i try to set VCP into Operation
on a Nucleo-H743ZI. Now i'm on the stage to set communication into operation.
After establishing connection to Win10 'hUsbDeviceFS.dev_state' goes
to 3 (USBD_STATE_CONFIGURED). This is the startpoint in my firmware to
try to send data to Host. For this i'm using the usb cdc interface function
uint8_t CDC_Transmit_FS(uint8_t* Buf, uint16_t Len).
On the Host side i'm using HTerm0.8.1Beta. If i start HTerm but do not open
connection to the COM Port to H7x my software recognise this because
CDC_Transmit_FS returns USBD_BUSY. If i open the COM Port in HTerm then
my firmware transmit data to Host (under certain circumstances).
Now i found out, if the size of data that i will be transfered is
lager than 24 Bytes, the HTerm tells me something like this:
...can't open COM Port because of internal error
Did anyone have experience with a behavior like this?
Any Remarks?
Kind Regards
Torsten
