使用Spartan 6运行microblaze作为中断驱动的从站工作不正常

嘿论坛，非常感谢这里的任何帮助。
我已经使用Spartan 6，microblaze和ISE14.4进行了数天的战斗 - 我已经将它配置为从属模式并且正在获取数据并使中断发射。
奇怪的是，中断在一个随机数字的字节后触发 - 我发送16位（并将其设置为xmit和rx 2字节，但中断仅在发送18到20个字节之后才触发，从不在16之后？
我减慢了时钟频率以及字节之间的时间，它仍然等待直到它看到18到20字节之间（所以我必须发送一个额外的字节，但它会让所有人感到困惑。甚至尝试了不同的数据包大小和它
只是想要额外数量的BIT（不是BYTES）。几乎看起来是随机的 - 我已经尝试了所有方法，包括重写xspi默认处理程序并获得相同的行为。甚至在这一点上尝试失去想法。
PS  - 在EDK中设置微纤维时使用SPISEL和MISO_O / MOSI_I /和SCLK_O  - 不确定_I和_O之间的区别是什么，只是简单的MISO / MOSI /和SCLK是 - 不认为它会有所作为吗？
有任何想法吗？
谢谢。



以下为原文

Hey Forum, really appreciate any help here.  I've been fighting this for days, using a Spartan 6, microblaze, and ISE14.4 -  I have configured it into slave mode and am getting data to it and having the interrupts firing.  The wierd thing is, the interrupt fires after a random number of bytes - I am sending 16 bits (and have it setup to xmit and rx 2 bytes, but the interrupt fires only after sending between 18 and 20 bytes, never after only 16???  I've slowed the clocked down as well as time between bytes and it still waits until it's seen between 18 and 20bytes (so I have to send an additional byte, but then it gets all confused.  Even tried different packet sizes and it just wants an extra number of BITs (not BYTES).  Almost seems random - I've tried everything including rewriting the xspi default handler and get the same behavior.  At a loss of ideas to even try at this point.
PS - using SPISEL and MISO_O/MOSI_I/and SCLK_O when setting up microblaze in EDK - not sure what the difference is betweeing the _I and _O and just plain MISO/MOSI/ and SCLK is - don't think it would make a difference?
Any ideas?  Thanks.