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USB middleware issue with CDC/VCP: only x packets receivable (HAL 1.1.0 and Host-Device_Lib 2.1.0)

Question asked by bs on Mar 26, 2014
Latest reply on Apr 28, 2014 by gabriel
1) with STM32_USB-Host-Device_Lib_V2.1.0:
I implemented a CDC/VCP device just accepting data and throwing it away (no further handling of the received data, just receive). After the receival of several packets, no further packets are received and the Endpoint is set to NAK. But after receival of the packet before the last one DCD_EP_PrepareRx was called to allow more data to come in. The DataOut Handler of the device class was no more called.

2) with Cube and HAL FW 1.1.0:
The device is by default (as generated by Cube) just receiving data but not handling it. After receiving the first packet (CDC_Receive gets called) no further receival is possible and CDC_Receive is never called again.

Has anyone an idea how to create a reliably functioning CDC device? I'm going to develop a far more complex device not just handling a few bytes per second. Is that possible with an STM32F427 + ULPI Phy?

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