Re: S-100 8086 Up and Runing

[Elsid <le...@swiftdsl.com.au>]

Hi John, Andrew and Robert and others,

Thanks for the good comments and tips. Yes I will cover the EPROM
windows when I've finish reprogamming. Mind you we once put a
programmed uncovered EPROM in the sun on a window ledge for a year
just to check how sensitive it was - no corruption. The house window
glass filters out most of the hard UV I think.
Sorry about the spelling error in the subject. (Runing instead of
running)

I'm running a purely N8VEM S-100 system except for the 12 slot Morrow
WonderBuss Backplane. I was using the N8VEM backplane but I now have
nine boards in this system and N8VEM board is only 8 slots. How's that
extension backplane coming on?

I have the N8VEM Z80 board in the bus (buss?) and am able to swtich
back and forth between 8086 and Z80 monitors without problem.

I uploaded some more photos to:
http://n8vem-sbc.pbworks.com/w/browse/#view=ViewFolder&param=8086

Unfortunately the last photo seems to upset the PBworks system and
boots you back to the home page. I can't delete the photo to clean
things up. I tried reloading the photo but the upload didn't progress.
The N8VEM website seems very slow to respond at the moment.

Have a Happy New Year
Leon

On Dec 27, 4:32 am, "John Monahan" <mon...@vitasoft.org> wrote:
> Delighted to hear that Leon. Always a relief to have somebody else
> independently get a board up and running in case I overlooked something.  K8
> is tricky. It decides when the pWR* & pDBIN signals actually become active
> on the bus. According to IEEE-696 they are only active AFTER pSync and
> pSTVAL go inactive.  You can sometimes "help" I/O boards get a jump on
> things if you let them out earlier (K2-3) and this run the bus at a slightly
> higher speed (or fewer wait states).  However some boards may not tolerate
> this.
>
> I have not played around with higher speed chips but I suspect you could
> squeeze 10MHz - possibly 11MHz out of the board  by playing around with
> things.  I have currently settled to 9MHz (2 I/O wait states) which is
> definitely stable with a 22 slot (Godboud active terminated motherboard).
> Be sure to place the CPU card in the middle of the bus and the 4MG Static
> RAM card at least 4 slots away.
>
> BTW, you might want to cover the windows  on the EPROMS. UV light from
> sunlight will eventually eat into them.
>
> John
>
> John Monahan Ph.D
> mon...@vitasoft.org
>
>
>
> -----Original Message-----
> From: n8vem...@googlegroups.com [mailto:n8vem...@googlegroups.com] On
>
> Behalf Of Elsid
> Sent: Monday, December 26, 2011 2:43 AM
> To: N8VEM-S100
> Subject: [N8VEM-S100:575] S-100 8086 Up and Runing
>
> Hi and Seasons Greatings.
> All the best to everyone and their families.
>
> I've just completed my S-100 8086 board.
> See photos at:http://n8vem-sbc.pbworks.com/w/browse/#view=ViewFolder¶m=8086
> Everything went smoothly except a missing K8 jumper 1-2 gave me some grief
> for a while.
> I have a V30 CPU and a 24MHz oscillator (8MHz clock) without any problems.
> I'll try  10MHz next when I get a crystal.
> Next step is to get CPM86 and MSDOS going.
> Thanks for another great board John and Andrew.
>
> Leon- Hide quoted text -
>
> - Show quoted text -