Subject: Re: 141-2 Bus troubles
To: John D. Baker <jdbaker@blkbox.com>
From: Bernd Walter <ticso@cicely8.cicely.de>
List: port-mvme68k
Date: 11/15/2001 18:03:48
On Thu, Nov 15, 2001 at 10:17:27AM -0600, John D. Baker wrote:
> Berndt Walter wrote:
>
> > [ MVME141 system-mode menu and errors deleted for brevity ]
>
> > The board has no onboard RAM beside of cache.
> > From what I understand addressing to VME RAM failed because of a
> > timeout, but bus abritation succeded?
> > And the RAM needs to start at address 0x0.
> > I have a MVME 224A-4 RAM board installed.
> >
> > I am not shure about the configuration and backplane requirements.
> > I have no documentaion about these boards.
>
> I think the MVME141 requires VSB/VMX bus for its main memory. VME
> access is only for peripheral I/O.
>
> The MVME141 board uses the MVME2400 "VSBchip" ASIC for VSB (VME
> Subsidiary Bus) interfacing. It uses the MVME6000 VMEchip for VME
> access just like the MVME147.
There are some strong signs that you are right.
Both mentioned chips are there.
And the RAM board has a VME and a VSB LED.
> You need a VME P2ac jumper cable made up of two female IDC DIN
> connectors and a short length of 64-conductor ribbon cable. The
> cable should be as short as possible--the spacing of the connectors
> should be no more than the slot spacing plus a little slack for
> insertion/removal.
OK - I have to inspect my Backplane if it has P2ac Support.
The case itself is not designed for it and I did not worry about
as I don't own any transition board.
Worst case it's a bunch of soldering work.
> Put the MVME141 in slot 1 of your chassis and the MVME224 in the next
> slot and plug the jumper cable between their P2 connectors on the
> rear of the P2 backplane.
>
> This is not a true VSB implementation, but a common 'hack' known as
> VMXbus which is sufficient in systems of VSB devices where there is
> only a single VSB master (such as a single CPU card and one or more
> memory cards). True VSB is a PCB backplane overlay which has a number
> of jumpers for the daisy-chained arbitration signals, etc.
>
> I will have a look at my MVME224 board later this evening and see if
> my switch settings will be useful for you (I have no docs for mine
> either).
>
> Hope this helps.
I'm almost shure it put me in the right direction.
--
B.Walter COSMO-Project http://www.cosmo-project.de
ticso@cicely.de Usergroup info@cosmo-project.de