Hello,
I am working with STM32F103ZFT6. I am working on a project where I have to respond to the Commands from Computer by sending a series of data bytes back to Computer from Micro-controller.
I have the Libraries and application software to do this job. But I have a recent requirement in which I have to send more than 75 bytes at one shot.
Earlier the data bytes were less than 60, so I was able to send without any problem.
The Functions which I am using to Load the data and send the data are as below.
1) UserToPMABufferCopy(uint8_tUSB_Tx_Buffer, ENDP1_TXADDR, uint16_tBuf_Count); 2) SetEPTxCount(ENDP1,uint16_tBuf_Count); 3) SetEPTxValid(ENDP1);
uint8_tUSB_Tx_Buffer - data bytes are in this buffer uint16_tBuf_Count - No of data bytes to be transfered.
These three functions are the library Functions.
This is strange that I am able to transfer less than 65 bytes easily. When I intend to traansfer more than 75 bytes. the connection from PC to Micro-controller is lost automatically and I have to do the connection and check. This is failing every time.
Can anyone please let me know the problem.
And also i dont have the proper datasheet for learning the USB details of STM32 like its registers, commands, etc..
Please help m e.. Its urgent..
Rgds Shankar