RiscPC startup/display problems
Tom Nicholls
In preparation for a return back to university, I had a go trying to
softload RISC OS 5's DHCP components on top of my 4.02 installation,
so I could attach it to the campus network. Unfortunately, this made
the machine hang during desktop boot.
On trying to bypass the boot sequence to undo the changes, I've now
somehow made the machine unable to finish booting *or* display
anything on my screen.
Current state:
PSU spins up, green POST display (briefly) appears on monitor, [if HD
is attached, it grinds a bit, orange HD light comes on continuously
for a while before going out], beep, keyboard lights flash, then
nothing. The monitor says "out of range". One basic problem is that my
monitor won't sync down to low-res modes. It's always been blank on
boot, but displayed the desktop perfectly well at 1024x768. Since I
now can't get the desktop at all, this is a problem.
Things tried:
* Shift-booting to bypass boot sequence
* Removal of hard disc to avoid dodgy boot sequence completely
* Delete-power on reset
* Powering on holding down "3" or "4" to configure a VGA-compatible
mode
* Powering on holding down "*" and blind typing *configure monitortype
[34], *configure mode 31 and *configure wimpmode 31
* Stripping the machine down to processor, one ram stick and no discs
and expansions and re-trying most of the above
Sadly I have no spare screens, having donated my lovely old Iiyama to
my mother-in-law.
One further quirk is that on stripping the machine down, I've
discovered that capacitor C2 on my Rev K strongarm card has at some
point been knocked off and was rolling loose at the bottom of the
machine! The legs have snapped so it's a difficult re-soldering job
but I'll give it a go.
So (finally!) my questions:
* Is there any way to persuade the machine to boot up in a VGA-
compatible mode so I can see what I'm doing?
* If it's getting to the "beep", what might stop it booting to a bare
desktop, when there's no drive (so no boot sequence)
* Any idea how I might get it running again?
Thanks,
Tom
Jess
ups.com>
Tom Nicholls <use...@tomnicholls.me.uk> wrote:
> Current state:
> PSU spins up, green POST display (briefly) appears on monitor, [if HD
> is attached, it grinds a bit, orange HD light comes on continuously
> for a while before going out], beep, keyboard lights flash, then
> nothing. The monitor says "out of range". One basic problem is that my
> monitor won't sync down to low-res modes. It's always been blank on
> boot, but displayed the desktop perfectly well at 1024x768. Since I
> now can't get the desktop at all, this is a problem.
It's not the old configure sync 0 problem is it?
(The plug and play signals from the monitor confuse the RPC into
thinking it has a non SVGA type monitor and drive it out of range.
Powering the machine up with no screen attached then plugging it in
sometimes works, allowing you to enter the correct details.
from http://www.riscos.org/csafaq/part2.html
N.B. The Risc PC can sometimes get confused when set to 'auto'
monitortype, resulting in a blank screen and no display on the
monitor.
If this happens, try re-configuring the CMOS ram settings to the
following and then reseting the machine.
*Configure Monitortype 4
*Configure Sync 0
*Configure Mode 40
These settings should prevent the monitor confusing the auto setting
of the Risc PC.
--
Jess Iyonix
Dave Plowman (News)
<2d80921d-1edc-47e3...@d17g2000yqm.googlegroups.com>,
Tom Nicholls <use...@tomnicholls.me.uk> wrote:
> * Is there any way to persuade the machine to boot up in a VGA-
> compatible mode so I can see what I'm doing?
Have you got a TV with a VGA socket? I have and it locks to the RPC even
after a reset - which my LCD monitor won't.
--
*I went to school to become a wit, only got halfway through.
Dave Plowman da...@davenoise.co.uk London SW
To e-mail, change noise into sound.
Tom Nicholls
> In article
> <2d80921d-1edc-47e3...@d17g2000yqm.googlegroups.com>,
> Tom Nicholls<use...@tomnicholls.me.uk> wrote:
>> * Is there any way to persuade the machine to boot up in a VGA-
>> compatible mode so I can see what I'm doing?
>
> Have you got a TV with a VGA socket? I have and it locks to the RPC even
> after a reset - which my LCD monitor won't.
Unfortunately not, though if I can't find any other way to see what's
wrong I'm thinking of getting a cheap VGA->S-Video adaptor box, which
I've been told may work.
Jess: Unfortunately, I don't seem to have had any joy with my reply
through Google, so here's the short version: Plugging in the monitor
after startup doesn't seem to help. Although I've tried blind-inputing
*configure sync 0 and the rest, it hasn't made a difference and I've no
way of knowing if it's gone in or not.
Thank you both very much for your help. Any other ideas?
Tom
Jess
Tom Nicholls <use...@tomnicholls.me.uk> wrote:
> after startup doesn't seem to help. Although I've tried blind-inputing
> *configure sync 0 and the rest, it hasn't made a difference and I've no
> way of knowing if it's gone in or not.
control-g gives a bleep, when you are on the command line. (And don't
forget, enter on a blank line takes you back to desktop).
If you don't get a bleep, it means you haven't got to the desktop.
If you have a spare VGA cable, it is possible to remove the pin that
carries the offending signal. (You'll need to look up which pin)
If you don't get a picture, then there are keys you can press on power
up to change the settings.
http://acorn.riscos.com/riscos3/37/37DiscImage/Manuals/Manual/BOOKB/BOOK_7.HTM
--
Jess Iyonix
Tony Moore
> In message <i8j0fg$dss$1...@news.ox.ac.uk>
> Tom Nicholls <use...@tomnicholls.me.uk> wrote:
>
> > after startup doesn't seem to help. Although I've tried
> > blind-inputing *configure sync 0 and the rest, it hasn't made a
> > difference and I've no way of knowing if it's gone in or not.
>
> control-g gives a bleep, when you are on the command line. (And don't
> forget, enter on a blank line takes you back to desktop).
>
> If you don't get a bleep, it means you haven't got to the desktop.
It could also mean that you've reached the desktop, but haven't pressed
f12, to access the command line, prior to ctrl-g, and config commands.
Tony
Tom Nicholls
> control-g gives a bleep, when you are on the command line. (And don't
> forget, enter on a blank line takes you back to desktop).
>
> If you don't get a bleep, it means you haven't got to the desktop.
No bleep, even with * power on, or waiting a long time and pressing f12.
I think that's fairly definitively not booting.
> If you have a spare VGA cable, it is possible to remove the pin that
> carries the offending signal. (You'll need to look up which pin)
I do have a spare cable, so I gave that a go. No joy.
I feel like I'm being drawn back to the missing capacitor on my SA card.
I've ordered a replacement 10uF surface-mount capacitor (aren't publicly
available circuit diagrams wonderful?) and will give that a go, if I
can't get hold of a spare processor card to test. Failing that, I'll
have to dig my parents' old RPC out of their loft and try replacing the
motherboard...
Thanks very much for your help, everybody - it's really narrowed things
down.
Tom
Alan Adams
Tom Nicholls <use...@tomnicholls.me.uk> wrote:
Before doing that, try borrowing the processor card. An ARM610 or 710
should just work (slowly) in place of a StrongARM. If that works you
know its the StrongARM card causing your problem.
> Thanks very much for your help, everybody - it's really narrowed things
> down.
> Tom
--
Alan Adams, from Northamptonshire
al...@adamshome.org.uk
http://www.nckc.org.uk/