STM32F105 / FS Bulk and Isochronous transfers

[firatparlak]

Posted on April 19, 2016 at 16:30

Hi,

I have a project that voice and parameter data will be transferred through Pc to STM32 and STM32 to PC. I want to use CDC to transfer parameters and isochronous to transfer voice. Is it possible to use isoc and bulk transfers in a STM32F105?There will be four endpoints. (CDC_In, CDC, Out, Isoc_In and Isoc_Out.) I derived CDC code from ST's VCP example and it worked.  Now, I want to add isochronous transfers. I see an USB Audio example for isochronous transfer, but there is only In_EP functions. Out EP function is empty.Is there any example to use both of bulk and isoc transfers in only one STM32F1x?Could you help me to use both of CDC and isoc?Best regards, #rx_fifo_fs_size #stm32f1-usb-bulk-isochronous #cdc-latency #tx0_fifo_fs_siz

[firatparlak]

Posted on April 19, 2016 at 16:46

When I want to send data greater than 64 bytes in bulk mode, there happens latency about 2-3 ms. I decrement the CDC_In_Frame_Interval to 1, but there is still latency. How can I eliminate the latency in here? If this latency will be eliminated, I can use only bulk mode, so the problem will be solved.

[firatparlak]

Posted on April 19, 2016 at 17:46

What could the highest values be below? Could I define 256 all of them?

#ifdef USB_OTG_FS_CORE

 #define RX_FIFO_FS_SIZE                          128

 #define TX0_FIFO_FS_SIZE                          64

 #define TX1_FIFO_FS_SIZE                         128

 #define TX2_FIFO_FS_SIZE                          0 

 #define TX3_FIFO_FS_SIZE                           0

[Tesla DeLorean]

Posted on April 19, 2016 at 21:00

What could the highest values be below? Could I define 256 all of them?

You have 1.25KB to play with, so presumably yes. These may have come from the 512 bytes in the F103