Posted on August 28, 2013 at 10:30
The green rectangle shows the correct behaviour USBH_BulkReceiveData issues one request and HCD_GetURB_State+HCD_GetXferCnt let me get the data.The red rectangle shows the wrong case: one call to USBH_BulkReceiveData causes two requests but I can get only the second, so I miss the first byte.Thank you for your help
Hello all,
I am using an stm32f105rc as an usb host to manage a cp2102 with freertos and st host stack.I found a problem with USBH_BulkReceiveData: sometimes it issues two bulk requests so I miss a byte.The connections are: one uart from pc to stm32, one usb from stm32 to cp2102, one uart from cp2102 to pc. stm32 routes bytes from its uart to usb and back, so I can connect two terminals on the pc and send strings to each other.I can sniff packets from stm32 to cp2102 and this is what I get:The green rectangle shows the correct behaviour USBH_BulkReceiveData issues one request and HCD_GetURB_State+HCD_GetXferCnt let me get the data.The red rectangle shows the wrong case: one call to USBH_BulkReceiveData causes two requests but I can get only the second, so I miss the first byte.Thank you for your help
