INT 2F - PC-DOS Econet v1.05 - PERFORM NETWORK OPERATION                        
	AX = C502h
	DS:DX -> control block (see #03036)
Return: AX = return code (see #03037) (same as returned in control block)
Note:	the interrupt-enable state will be preserved, but interrupts may be
	  enabled during processing of this function
SeeAlso: AX=C500h


Format of Econet control block:
Offset	Size	Description	(Table 03036)
 00h	DWORDDoubleword; four bytes.	 Commonly used to hold a 32-bit segment:offset or selector:offset address.	-> command block (see #03038)
 04h	WORD	length of transmit data block
 06h	DWORDDoubleword; four bytes.	 Commonly used to hold a 32-bit segment:offset or selector:offset address.	-> transmit data block
 0Ah	WORD	length of reply block (set to 0000h prior to call)
 0Ch	DWORDDoubleword; four bytes.	 Commonly used to hold a 32-bit segment:offset or selector:offset address.	-> reply block
 10h	WORD	return code (set to 0000h prior to call) (see #03037)
 12h	DWORDDoubleword; four bytes.	 Commonly used to hold a 32-bit segment:offset or selector:offset address.	reserved for Econet use


(Table 03037)
Values for Econet return code:
 0000h	successful
 0001h	bad command in command block
 0002h	no handles left
 0003h	bad handle
 0004h	bad argument in command
 0005h	buffer too small
 0006h	kill condition failed
 0007h	control block in use
 007Fh	command aborted
 01xxh	retryable board error XXh
 02xxh	fatal board error XXh
 0300h	invalid subfunction number in AL
 0301h	timeout
 03xxh	other driver errors
SeeAlso: #03036


Format of Econet command block:
Offset	Size	Description	(Table 03038)
 00h	BYTE	command code (see #03039)
---command 00h---
 01h	BYTE	direction (00h = read initialization data, 01h = set init data)
 02h	WORD	"TxCB" transmit control block size
 04h	WORD	"RxCB" receive control block size
		Notes:	TxCB and RxCB are always the same size in v1.05,
			  permitting any CB to be used for either receive
			  or transmit
			this command should not be used by applications to
			  set the buffer sizes
 06h  6 BYTEs	padding (0)
---command 01h---
 01h	BYTE	port number (00h = receive on all ports)
		if the RxCB is opened for RPC, the port number indicates the
		  allowable RPC (see #03040)
 02h	WORD	station number (FEFFh = broadcast)
 04h	BYTE	RPC flags
		bit 7: CB is open for RPCs only
		bit 6: restrict to RPC number given in next field
 05h	WORD	RPC number
 07h	BYTE	timeout in 1/2-second units (00h = never)
		if a timeout occurs, the RxCB can still receive data, and may
		  generate another event after the timeout unless it is
		  explicitly killed
 08h  4 BYTEs	padding (0)
---command 02h---
 01h	BYTE	control byte
 02h	BYTE	port number
 03h	WORD	station number
 05h	BYTE	number of retries
 06h	WORD	length of data to be sent (bits 14-0), 0000h allowed
		if bit 15 is set, no data will be transferred, but this field
		  will be updated (needed for peeking)
 08h	DWORDDoubleword; four bytes.	 Commonly used to hold a 32-bit segment:offset or selector:offset address.	-> destination address on remote machine
---command 03h---
 01h	BYTE	Control Block HandleA short identifier, usually a small integer or a pointer, for some other object which is maintained or controlled by the operating system or environment; a particular handle may be valid system-wide or may have meaning only for a particular process.	 See also File Handle.
		FEh first filled-in RxCB
		FFh first TxCB which has been sent
 02h 10 BYTEs	padding (0)
---command 04h---
 01h	BYTE	Control Block HandleA short identifier, usually a small integer or a pointer, for some other object which is maintained or controlled by the operating system or environment; a particular handle may be valid system-wide or may have meaning only for a particular process.	 See also File Handle.
 02h	BYTE	kill condition
		00h always
		01h kill only if bit7 of control byte is clear
		81h kill only if bit7 of control byte is set
 03h  9 BYTEs	padding (0)
		Notes:	control blocks are not freed until explicitly killed
			because all TxCBs for a given destination are stored
			  on a separate subchain, it is necessary to kill all
			  failed TxCBs to a given destination before any new
			  ones are opened to that destination
---command 06h---
 01h	BYTE	Control Block HandleA short identifier, usually a small integer or a pointer, for some other object which is maintained or controlled by the operating system or environment; a particular handle may be valid system-wide or may have meaning only for a particular process.	 See also File Handle.
 02h	WORD	starting byte within CB to read
 04h	WORD	number of bytes
		if 0000h or greater than remaining bytes in CB, return all
		  bytes from starting byte to end of CB
 06h  6 BYTEs	padding (0)
---command 07h---
 01h	BYTE	subfunction
		00h-0Fh get/set M/C type (bit N=1 indicates to set byte N)
			four data bytes
		10h get station number
		11h set station number
		12h get Tx pause in 5ms units (default 20)
		13h set Tx pause
		14h get software version numbers
		16h get event enable mask
		17h set event enable mask
		18h get number of non-volatile bytes available
		80h+2N get non-volatile byte N
		81h+2N set non-volatile byte N
 02h	var	new data
Note:	all command blocks should be padded to twelve bytes with zeros if
	  needed
SeeAlso: #03036


(Table 03039)
Values for Econet command code:
 00h	initialize
 01h	open receive
 02h	open transmit
 03h	poll
 04h	kill
 06h	read
 07h	get/set system parameters
SeeAlso: #03038


(Table 03040)
Values for Econet RPC type:
 00h	all
 81h	peek
 82h	poke
 83h	remote JSR
 84h	remote procedure call
 85h	OS procedure
 86h	Halt
 87h	Continue
SeeAlso: #03038


Format of Econet Reply Block (command 00h):
Offset	Size	Description	(Table 03041)
 00h	WORD	TxCB size (default is 0500h, the maximum Econet packet length)
 02h	WORD	RxCB size
 04h	BYTE	number of TxCBs allocated	
 05h	BYTE	number of RxCBs allocated	
SeeAlso: #03036,#03042,#03044


Format of Econet Reply Block (commands 01h,02h):
Offset	Size	Description	(Table 03042)
 00h	BYTE	control block handle
SeeAlso: #03036,#03041,#03045


Format of Econet Reply Block (command 03h):
Offset	Size	Description	(Table 03043)
 00h	BYTE	CB number (when wildcard specified for poll)
 01h	BYTE	control
		(RxCB) 00h until received, then Sent Control byte
		(TxCB) transmit status
		    bit 7: transmission pending
		    bit 6: transmission failed
		    bits 3-0: error number
 02h	BYTE	Port number
 03h	WORD	station number
 05h	WORD	length
 07h	WORD	0000h
SeeAlso: #03036,#03041,#03044


Format of Econet Reply Block (command 06h):
Offset	Size	Description	(Table 03044)
 00h  N BYTEs	data read from network
SeeAlso: #03036,#03043,#03045


Format of Econet Reply Block (command 07h):
Offset	Size	Description	(Table 03045)
 00h  N BYTEs	returned information
SeeAlso: #03036,#03044