new computers... Finally!

From: Ethan Dicks <erd_6502_at_yahoo.com>
Date: Fri Apr 4 13:33:00 2003

--- Witchy <witchy_at_binarydinosaurs.co.uk> wrote:
> > I have an Amiga 500+ with an
> > A520 adaptor.
> > When i tuned it to my T.V. it just stays dark blue, but says
> > there's a signal.

Have you tried plugging into a monitor? Do you _have_ a compatible
monitor (probably not if you are using it with a TV).

It's not clear to me if the problem is with your CPU or with your A520.

> > The animated hand thing doesn't even appear! Help! And I don't
> > have the poster about the connections!!!

The "hand" wasn't animated. It was a simple still picture of a hand
holding a disk. Later ROMs (2.x) used an animated diskette inserting
itself into a floppy drive.

> If your screen stays blue you have a fault in one of the custom chips
> (AGNUS, PAULA or DENISE) so it's repair time!

I don't recall ever seeing blue. *Green* was the one you saw most
often - typically caused by the Agnes chip working its way out of
its socket (later units had a small spring-steel keeper over the
top of the chip). Green meant that something was wrong with accessing
CHIP RAM (*most* often a bad/loose Agnes, but not exclusively). The
other common color was gray/white which just meant that the lowest level
stuff worked, but it wasn't loading/running OS code. I have seen Red
and Yellow, but they aren't very common. Black, of course, with no
color shifts at all, means that nothing is happening (bad PSU, bad CPU,
bad ROM...)

> Also, if it's a 500+ you'll
> have version 2 ROMs which have an animated floppy disk, not the old 1.3
> 'badly drawn hand'.

That sounds right (I never had a 500+)

Is is possible that the "blue" you are seeing isn't really a true "blue"
(as in it's a black screen with the colors/brightness turned way up; or
more of a deep blue, almost maroon, which could be the 2.0 background
color with no disk image/text on it?) If it's a primary, saturated,
bright blue (bluer than the desktop of a Windoze machine), then it might
be a signal from the ROMs that something is wrong. A darker, muddy blue
is probably something else.

If, for example, the Denise chip is bad, or the external network that
converts its 12-bit color bus to analog signals is bad, or the A520 is
bad, perhaps it's a white screen with only the Blue component showing.

Describe how the power LEDs flash - that tells a story, too.

-ethan

>
> cheers
>
> --
> adrian/witchy
> www.binarydinosaurs.co.uk - the online computer museum
> www.snakebiteandblack.co.uk - monthly gothic shenanigans
Received on Fri Apr 04 2003 - 13:33:00 BST