Disable Exponential Backoff (retry) on Ethernet?

[Len Gross]

I'm doing some protocol development and it is convenient to start it on
Ethernet.  I will need to send a packet to the Ethernet device and only have
it be sent once, even if there is a colision.  (Higher levels in the
protocol will detect the failure.)  I've searched quite a bit, and haven't
found any place that talks about this.   Are there any hardware cards, or
drivers, that let me turn off the backoff/retry behavior?

-- Len