Bits | Field Name | Description |
5 | DMAERR | 1 = USB requests a DMA access to read a new BDT, but is not given the bus |
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| before USB needs to receive or transmit data. |
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| • If processing a TX transfer, this causes a transmit data underflow condition. |
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| • If processing an Rx transfer, this causes a receive data overflow condition. |
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| This interrupt is useful for developing |
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| microprocessor and USB to minimize bus request and bus grant latency. |
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| OR |
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| 1 = a data packet to or from the host is larger than the buffer size allocated in the |
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| BDT. The data packet is truncated as it is placed into buffer memory. |
4 | BTOERR | 1 = a bus turnaround |
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| 0 = a bus turnaround |
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| The USB uses a |
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| token and data phases of a SETUP or OUT TOKEN or the data and handshake |
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| phases of a IN TOKEN. If more that |
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| EOP before a transition from IDLE, a bus turnaround |
3 | DFN8 | Data Field Received Not 8 Bits |
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| The USB Specification 1.0 states that the data field must be an integral number of |
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| bytes. If the data field is not an integral number of bytes, this bit is set. |
2 | CRC16 | CRC16 Failure |
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| 1 = data packet is rejected due to a CRC16 error. |
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| 0 = data packet is not rejected due to a CRC16 error. |
1 | CRC5\EOF | Error interrupt with two functions. |
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| • USB is in peripheral mode (HOST_MODE_EN=0): this interrupt detects a CRC5 |
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| error in the token packets generated by the host. If set, the token packet is |
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| rejected due to a CRC5 error. |
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| • USB is in host mode (HOST_MODE_EN=1): this interrupt detects |
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| (EOF) error conditions. This occurs when the USB transmits or receives data |
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| and the SOF counter is zero. In this mode, this interrupt is useful for developing |
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| USB |
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| start of the next frame. |
0 | PID_ERR | PID check field failed. |
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