Format of packet driver parameter table:
Offset	Size	Description	)
 00h	BYTE	major revision of packet driver spec driver conforms to
 01h	BYTE	minor revision of packet driver spec
 02h	BYTE	length of this structure in bytes
 03h	BYTE	length of a MAC-layer address
 04h	WORD	maximum transfer unit, including MAC headers
 06h	WORD	buffer size for multicast addr
 08h	WORD	number of receive buffers (one less than back-to-back MTU rcvs)
 0Ah	WORD	number of transmit buffers
 0Ch	WORD	interrupt number to hook for post-EOI processing, 00h=none