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[darksun9210]

Hello again!
well, its one of those days again, battling 20+ year old hardware

i have,
a rev5 A500, with 1.3rom, 512kb chip, 512kb "slow" fast, with battery backed up clock, and a broken floppy eject button. all was working well, but having to use a screw driver to eject floppys annoyed me.

so ordered a new floppy drive, while i was at it, a clock port adapter, an ECS denise, and a 3.1 Rom - but never got round to fitting them.
then on ebay, recently got a GVP HD8+ (the stuff of childhood dreams - there was no way i h3ll i could have afforded one back in the day, much less the drool worthy GVP 530), and a supra turbo28. (hard to find 030 accelerators for 68000 based machines these days...)

the GVP and Supra arrived today. so in a fit of childhood excitment, i (stupidly) installed everything. all at once.
except the clock port adapter doesn't fit a rev5 A500 mainboard. there are some components around the CPU that get in the way - so left that out.

anyway switch on. flash of white, then nothing. not even a power light

pulled off the supra and the GVP. flash of white, then nothing - again, no power light.

switch the 3.1rom for the 1.3rom. hand holding disk success.... ...for about 5-10 seconds, then guru'd with a software failier.

so the 3.1rom is duff...

switch off then back on. same thing, so at least this is repeatable.

could be the 1.3rom doesn't like the ECS denise.

swapped out the ECS denise, for the OCS denise.
more stable. boots off a random amiga format floppy disk, then the graphics get corrupt and the machine reboots.
power light flickering randomly, floppy sounds like the machine is rebooting at random. worried and switched off quick!

Pull the denise chip, and for the h3ll of it, switch on. machine boots from floppy with no denise! .. for about 5 or so seconds before the random reboot thing kicks in.

argh!

have noticed some corrosion on the 3rd pin connector on the left in the denise socket on the CPU side. what is this connector?

i'm using an A1200 PSU for convenience, may this possible lack of power be a problem?
i'm guessing the 3.1rom is dead?
i'm also guessing the 1.3rom doesn't like the ECS denise?

i have tried it with the GVP attached, and things seem a little more stable, hence the power query,
but its only a matter of time before the graphics get corrupt. and i mean really corrupt. its like the ramDAC is screwed, as its that fast. its not just a "dump random chip memory area to screen" cos i know what that looks like - all blocky and organised, and pixels move around while loading data.

someone tell me she's not dead... :boohoo:

--edit--
sorry for the essay

[Argus]

I doubt anything is *dead* Try cleaning all the socketed chips and their sockets with isopropyl alcohol and reseat them all (making sure they are oriented correctly of course). Once the machine boots from a stock configuration, try adding extra hardware bits one at a time (leave the case open while experimenting. It could also be the Supra doesn't like the GVP or vice versa.

[amiga92570]

I would get a heavy duty power supply. At least a 500 power supply unit. The 1200 was barely enough on its own. Also make sure the floppy power and cable are properly attached. You didn't by chance insert rom backwards did you? :-?

[melange]

I think it's the revision 5 A500's that needed a Jumper soldered from pin 1 to 31 on the 3.1 ROM to make it go. I'm sure I had to do that to mine in the old days.

Anybody agree?

[darksun9210]

thanks Argus,i needed that - a nice measured response. :-) its about 1am and i'm tired, so not prone to rational thought i guess.

anyway, i'll try to clean the chips, and sockets and go with baby steps at trying the basics. but it can wait till tomorrow. i need sleep. night all!

[darksun9210]

cool, thanks for the tip Melange, i'll look that up

[melange]

Actually I'd also check your floppy cable is correctly seated and properly positioned on all pins. Check for pin 1 to red wire on the ribbon cable etc... Also check the powercable to the floppy is connected properly.

The power light flickering randomly reminds me of floppy drive problems I have had.

[darksun9210]

amiga92570, i did think that... i'll pull the A500 PSU out the bottom of the cupboard tomorrow, thanks for the pointer though :-)

[darksun9210]

floppy drive huh? well, the replacement drive i had bought seems to be a modified PC drive... i'll put the old one back in and see what that does. i wouldn't have even thought of that...

[darksun9210]

ok. i quickly sat the old floppy drive ontop of the new one and plugged it in.
she seemed to boot off floppy (amiga format pagesetter coverdisk) and get to a workbench, even told me it was the 18-Aug-78 while booting.
got to workbench and double clicked on the floppy. seemed ok, then it stuttered and the screen flickered, and i got the error "you MUST replace volume pagesetter in device 0!!!" clicked ok, another screen glitch, and another requester. clicked ok. stutter, loaded the rest of the icons.
one thing did bother me, i may be reading this wrong, as its been a long while since i read a 1.3 menubar memory display, but it looks like the extra ram isn't working either... but if that wasn't working, how'd it get the time and date while booting?
*headbutt wall*
hmmm... more investigation required tomorrow. sleep now.

[Tomas]

one thing did bother me, i may be reading this wrong, as its been a long while since i read a 1.3 menubar memory display

What does it say?

[darksun9210]

erm, 400000 initially, then went down to 396somethingsomethingsomething with a window open. thats not good if there is an xtra 512k in there right? - its now totally stock with only the trapdoor memory expansion..

[Tenacious]

It sounds like your system clock reset back to the default date, like it's not reading the rtc on the ram expansion in the trap door. Has this board been disturbed, is it seated correctly? Mine was encased in a metal shield and the battery is in there. Have you inspected or replaced this battery?

Will OS3.1 work with 512K of chip and 512K of fast/slow memory? I converted all of my A500s to 1M of chip before 3.1 was released.