Hello,
I am interested to make USB HID HOST which can communicate with custom hid device instead of mice or keyboard.
For that I have to send data to that custom hid device. I have used below fuction for dataout USBH_InterruptSendData (pdev, (unsigned char *)&HID_Machine.buff, HID_Machine.length, HID_Machine.hc_num_out);
I am only doing out transaction form Host(STM32) to device. Everything is perfect and working fine up to 14th frame but 15th frame get corrupted, I have analyzer showing "child has an error". So I am unable to understand the cause of issue, is it memory overflow at host?
If I continue data transmission with new data then host is sending old data packet onwards
I used dual core example for ST and modified USBH_HID_Handle() as below (Only two cases are shown here)
case HID_SEND_DATA:
while(USB_OTG_IsEvenFrame(pdev) == FALSE);
USBH_InterruptSendData (pdev, (unsigned char *)&HID_Machine.buff, HID_Machine.length, HID_Machine.hc_num_out);
HID_Machine.state = HID_BUSY;
HID_Machine.timer = HCD_GetCurrentFrame(pdev);
break;
case HID_BUSY:
if(( HCD_GetCurrentFrame(pdev) - HID_Machine.timer) >= HID_Machine.poll)
{ HID_Machine.state = HID_SEND_DATA; //Retry++; //1 }
else if(HCD_GetURB_State(pdev , HID_Machine.hc_num_out) == URB_DONE) //last transaction was successful or not(USB request Block)
{ HID_Machine.state = HID_GET_DATA;
BD_Data_Sent_Flag=1;
}
else if(HCD_GetURB_State(pdev, HID_Machine.hc_num_out) == URB_STALL )
{
if( (USBH_ClrFeature(pdev, pphost, HID_Machine.ep_addr, HID_Machine.hc_num_out)) == USBH_OK)
HID_Machine.state = HID_SEND_DATA;
} }
Please help...
Hi Krunal,
> I have analyzer showing "child has an error".
Do you mean a hardware protocol analyzer? What does "child has an error" exactly mean? Packet format error (such as CRC, EOP timing or no response)? Which packet causes the error, OUT, DATA0/1 or ACK?
Tsuneo
Thanks Tsuneo for reply.
I don't know meaning of "child has an error" but it is showing by beagle analyzer for OUT transaction. Anyway all problems were resolved with 2.1.0 library. Now I am able to transmit data to the device without any problem.
Using 2.0.0 library, ST told me that "you are transmitting data in asynchronous mode instead of synchronous mode". I don't go into the details with this type of configuration but definitely I am interested to understand it in future.
Krunal
Hi Krunal, Can you help me. Thank you.