🚀 go-pugleaf

I am trying to learn how to program using a packet driver, and am having a
very difficult time trying to set up a handler using the "access_type" call to
packet driver.  I have some code below, which has been reworked numerous times,
always with the same results.  I get a valid handler back with no errors, but
when I ping my pc from a unix box, the far assembly procedure MyRoutine does
not get called.  (I am using Turbo Pascal 6.0, BTW.  I know C would be better,
but I do not have a decent C compiler at home [yet]).

A few notes: 
	I have tried TypeLen (CX) set to 0, which, according the packet driver
	specs, should call MyRoutine _every_ time a packet is received. 

	I have tried byte-swapping the word constant IP--no difference.

	I _can_ get the thing to generate errors if I purposely set illegal
	if{Type,Class,Number} values.

	All the other basic packet driver functions (AH={1,2,3,4,5,6,7}) work
	fine.

Here is the routine (which has become a bit messy over time).  I have coded it
entirely in assembly, BTW, with no luck.

I would greatly appreciate any help.  I'm pulling my hair out over this.



function pkt_AccessType;

var
	Error: byte;
	TypeSeg, TypeOfs, RecSeg, RecOfs, Handle, Temp: word;
	r: Registers;

begin
	RecSeg := Seg(MyRoutine);	{MyRoutine is a far assembly procedure}
	RecOfs := Ofs(MyRoutine);

	TypeSeg := Seg(IP);		{IP is a word containing $0008}
	TypeOfs := Ofs(IP);

	asm
		push	DS		{I have a hunch that this is needed}
		mov	AX,RecSeg	{RecSeg}
		mov	ES,AX
		mov	DI,RecOfs	{RecOfs}

		mov	AX,TypeSeg
		mov	DS,AX
		mov	SI,TypeOfs

{I have set the following to constants instead of the passed parameters here}
		mov	AL,1		{ifClass-DIX Ethernet}
		mov	BX,14		{ifType-WD8003}
		mov	DL,0		{ifNumber}

		mov	CX,2		{TypeLen}

		mov	AH,2
		int	$60
		pop	DS

		jnc	@NoError
		mov	Error,DH	{Error found}
		jmp @exit

	 @NoError:
		mov	Error, 0
		mov	Temp,AX
	 @exit:
	end;
	pkt_AccessType := Temp;	
	pkt_Result := Error;		{pkt_result is a global variable}
end;
-- 
------ Dave Denson                      (Preferred:  densond@storm.cs.orst.edu)
Computer Sciences Corporation                       (densond@heart.cor.epa.gov)
US EPA Corvallis Environmental Research Lab
The above opinions are by no means whatsoever endorsed by US EPA, CSC, or OSU.