CVS have defined a dual port structure that is fixed across their entire range of slave cards. This file defines that structure.

Tasks can have there activation area in dual port. This makes it simple for the master to start a task in the slave. Quite neat really.

 
	HOST
	\ these must be the first dual port varaiables defined
	'tport @ _#RTI1000_dual_port_base  ??=

	$20 CONSTANT #port_tube_max

	port_variable %port_running         ( Set to 12345678 by slave)
	port_variable %port_pbase
	port_variable %port_offset
	port_variable %port_wake            ( value to wake a task)
	port_variable %port_table_disk
	port_variable %port_(file_table)   \ this is $heading in BVP, 
	port_variable %port_($version)
	port_variable %port_software_version

	$20 _#RTI1000_dual_port_base + 'tport !
	port_variable %port_ticks			( supplied by master, thats not us)
	port_variable %port_who             \ slave can ask master what slot number it is in
	port_variable %port_init_where		( let others see where init up to)
	port_wvariable %port_software_type 
	port_wvariable %port_interface_version 

	\ next $10 bytes are preserved for tcp/ip control area.
	\ probable won't be needed as packet will be transfered using the big dual port buffer.
	$30 _#RTI1000_dual_port_base + 'tport !

	$40 _#RTI1000_dual_port_base + 'tport !
	\ The varibles are set and the master interrupted.
	port_wvariable %port_i_terminal
	port_wvariable %port_i_disking
	port_wvariable %port_i_^ced
	port_wvariable %port_i_logoff
	port_wvariable %port_???  
	port_wvariable %port_???
	port_wvariable %port_???
	port_wvariable %port_i_?who \ request fron slave to get slot number 
	                            \ tcp/ip will need this support.


\ application
	port_wvariable %port_i_data
	port_wvariable %port_i_command
	port_wvariable %port_i_error
	port_wvariable %port_???
	
	port_wvariable %port_???
	port_wvariable %port_???
	port_wvariable %port_???
	port_wvariable %port_i_file

	$60 _#RTI1000_dual_port_base + 'tport !
	port_variable %port_i_unit



	$80 _#RTI1000_dual_port_base + 'tport !
	\ PC database pointers 
	port_variable %port_I1addr
	port_variable %port_I1num
	port_variable %port_I2addr
	port_variable %port_I2num
	
	port_variable %port_I4addr
	port_variable %port_I4num
	port_variable %port_O1addr
	port_variable %port_O1num
	
	port_variable %port_O2addr
	port_variable %port_O2num
	port_variable %port_O4addr
	port_variable %port_O4num
	\ $B0
	
	$100 _#RTI1000_dual_port_base + 'tport !

	\ This descibes the data structure used to transfer file data
	\ between the master and slave. The transfers are handled by a task
	\ in the master. The task is started by an interrupt routine in the master.
	\ The master will wake the slave task up by writing to it's activation area.
	\ Once upon a time all slave tasks had there activation area in dual port,
	\ this is no longer the case as task can be created out of free buffers.
	\ To overcome this there is now a task in the slave that looks after disk
	\ services for all slave taks. This taks has a activation area in dual
	\ port memory.
	\ All this is hidden under the rti device.
	0 
	DUP	CONSTANT	#flbus_link 4+     ( for master)
	DUP CONSTANT	#flbus_source 2+   ( for master)
	DUP CONSTANT	#flbus_facility 4+ ( for slave)
	DUP CONSTANT	#flbus_count 2+    ( for slvae)
	DUP CONSTANT	#flbus_buffer 4+   ( for slave)
		CONSTANT	#flbus_length

port_variable %port_file_table #flbus_length 4 - port_allot
port_variable %port_tube_control>  #port_tube_max 4* port_allot

\ The BCM522 expects this buffer to be the length of the maximum
\ ilan packet. It does give the best performance.
port_create %port_buffer #ilan_packet_max port_allot