Path: utzoo!attcan!uunet!mcsun!sunic!tut!santra!santra!jtv
From: jtv@kampi.hut.fi (Jukka Virtanen)
Newsgroups: comp.arch
Subject: Re: Am7990 LANCE chip
Message-ID: <JTV.90Jan13071248@kampi.hut.fi>
Date: 13 Jan 90 05:12:48 GMT
References: <2496@ifi.uio.no>
Sender: news@santra.uucp (Cnews - USENET news system)
Organization: Helsinki University of Technology, Finland
Lines: 32
In-Reply-To: arneme@sfd.uit.no's message of 12 Jan 90 16:21:48 GMT


	Hi. 

> I am trying to write a device driver for the Am 7990 LANCE chip. The driver
> is going to be a part of a small standalone kernel for the MC68030. The on
> board (We are using the MVME 147 boards) MC68851 MMU is not activated.

	I am writing a bsd 4.3 driver for the Lance chip
	on the uVax-3300 cpu board (VAX_650)...

> The mode part of the initialization block is set to 0x0000, the physical
> adress is set to my address which is 8:0:3E:20:1:99. The logical adress
> filter is set to all zeros, and the Receive Descriptor Ring Pointer (RDRP)
> (bits 0-23) is set to the adress of the first of 8 receive descriptors
> allocated contigiously in memory. (the rlen part of the RDRP is set to
> 0x3).The TRDP is set accordingly (also have 8 transmit descriptors). RMD0 and
> RMD1 is set to reflect the address where the receive descriptors are, and
> the OWN bit is set to 0. RMD2 (bcnt) is set to -1518. TMD0 and TMD1 is set
> to the address of the transmit descriptor entries.

	I do not get it... If you set the OWN bit of the receive
	descriptors to 0, it means that the LANCE can not use them.
	Try setting the OWN bit to 1 and watch it fly. Of course,
	the OWN bit of the transmit buffers need to be 0 until you
	fill them with something.

	Also check the ring-pointer alignment (needs to be 8)
	and that you set the csr[1,2,3] values after setting the
	STOP bit before you START it again.
	
					Juki
					jtv@hut.fi